I think that holds here. These are not statistcs from well controlled studies, just observational statistics from general folk, how often they report getting hurt while lifting weights

I'll say on this the same as I say about crossfit.

Worse for gains than weight training, worse for cardio than cardio. The best way to combine both.

You have pointed out the biggest benefit of this style of training: Some people really really like it. From the fact that it is a trope that crosfitters talk about it all the time, I take that crossfit is really good at getting people to stick to the habit. I have recommended it to people whose main worry was "I don't know if I'll enjoy lifting weights that much".

The buzz is real

Depends on how off the beaten path you go. I can give for each of the movement patterns above my best recomended exercises, and how good they are compared to the gold tier. 

[legs] : Lunges, Sissy squats, single leg squats and so on, if you add some weight to your back. I think these are great. Kind of annoying, and yo might only have one or two you are in the correct strength range to do.
[side delts]: Pretty much no way to train without a heavy thing you can hold in one hand. One set of adjustable DBs solves this.
[H pull]: Inverted rows are the only thing you can set sup, but they're really messy, so can't train this super well. With DBs you can do one arm or two arm DB Rows.
[H Pull]: You need a pull up bar. If you're not strong enough for pullups/chin ups (at least 5), cheap bands as assistance will get you there. No lower tech way to train this.
[H Push]: From kneeling push ups, to deficit push ups, the low tech solutions are great and probably accomodate any strenght level you have. 
[V Push]: The most redundant of my 6 classes. You can push heavy things vertically if you have them, otherwise i can't think of a way.

Is working out half your body well and neglecting the other half better than not working out? hell yes. WIll anything bad happend from being "inbalanced"? Nothing beyond maybe looking unbalanced

Yeah. Progression will be really weird when you start by yourself. 
Sometimes you'll be 20% stronger than last workout on the same exercise, sometimes 20% less (because you might have improved your technique).

If you are not, on average, getting stronger, you are probably not gaining muscle. Don't goodhart, letting your technique focus slip away.

Progression changes a lot from one exercise to the other. You can probably add 5lbs every time you deadlift for the first 3 months. However I've been doing DB Lateral raises for 3 years and I'm about to move on to the 20lbs.

My practical advice? 

• Keep track of the weights you're using, apps like strong do this well. Anytime you select a lift, it shows you how much you did it with last time.
• As a beginner, stop every set when you are not confident you can maintain good technique on the next set. You'll be farther from "true muscular failure" than someone who is more accostumed with the lift, but that's ok.
• For every exercise, have a range of repetitions. Say you're doing squats for 5-8 reps. Perform the set as described above. If you get less than 5, next sets use 10% less weight. If you get more than 8, next time use 10% more weight.

Those are great goals. 
If you want to be "lifting your husband" strong, look up the starting strength squat and deadlift guides. 
For upper body exercise suggestions, I think the list above is great.

For injury risk, I would really not worry, given the injury statistics are so low, and they are from people who DON'T focus on technique. The median gym goes is a 30yo guy swinging as much weight as possible around, and he's mostly fine.

As far as technique goes, define failure as "I can't do another rep without changing technique" and you reduce your chance of injure drastically.
 
For the exercises you're doing now, I'd say there is a lot of "redundance / over-optimization", e.g. the leg press will train both your adductors and abductors. If you want to do 2 leg exercises instead of just one (like I suggested in the post), I'd pick one form each category):
[squat] : Leg press, Back Squat, Front squat, split squat, hack squat, smith machine squat, dumbell-on-shoulder squat, goblet squat
[hinge] : Deadlift, Romanian deadlift, good Morning, reverse lunge.

 

For "optimization" I totally agree. This was not the goal here, but yeah I think if you can only do one you should lift, as it will improve your cardio to above baseline levels, but doing both is probably better than just lifting

You can find videos where girls deliberatly flexing can evoke bad reactions, but those same girls are totally fine when not flexing.

I have seen one example (so infer many exist) of a very gifted chinese lady living in the us who was quite muscular, and her wedding photographer photoshoped her legs to be skinnier. I have no idead how cultures other than the western monoculture operate with this, and probably should make it clear my statement is somewhat tonge and cheek, or add this nuance to it.

The thing to keep in mind is, lets say with 10 years of dedication you could get to a place where you'd be "too muscular". 

1 - You'll notice before you get there and just stop. Muscle growth is extremelly slow

2 - You can reverse. 2 months of not training and dieting will take a lot of muscle off

If your gym has a good selection of machines, you can totally get really jacked just using them, see my above comment for Barbells vs Dumbells. My first questions to you would be how you're training your legs and abs since machines for those can be rarer.

I should double down on the point that injury should not be on my mind. Here are some factoids since I can't tread them into a coherent narrative very quickly:
* When the median american lifts weights, aka someone who is much more careless than yourself, he gets injured way less often than in any other sport.
* Even for injuries that happen in the gym, accidents like tripping and weight falling on you make up a bigger share than what we think of as "injuries". Wear shoes, don't walk around weights looking at your phone, be sensible etc.
* Injuries are most often not a consequence of "misperforming an exercise once". They are rather the result of bad programming. Every rep you do with your legs hurts your knee a little bit, and it can heal some amount per week. Injury comes when you do more (load, reps, sets, speed) in aggregate than you can handle, which is really difficult for a beginner, and for someone training for not that much per week.
* Acute injury, aka when you break something during a lift, should be a worry only for the strongest among us. It's just math. Your muscles can produce some amount of force, which your tendons must be able to transfer without snappin. For normal humans, your muscles are nowhere near strong enough to do this. WIth years of strength training (and PEDs which strengthen your muscles without strenghtening your tendons), you can maybe get there. 

My advice is to be mindful of technique when learning a new lift, film yourself or ask someone to watch if you can, and make sure it looks the same as in the video.

Advice for moving from machines to free weights? Pick like 2 or 3 free weight exercises that look cool to you / are hard do do with machines and swap them into your program. Rinse and repeat after months. You may have many worries, and I can dispell most of them if you lay them out.

I also use strong, I have the premium membership. I looked into all the other apps, their features are not beter tracking afaik, but algorithms that create programs for you, or just access to pre-made programs

There is no broad difference. This is also true of the machines vs free weights question. Many trials have investigated this, and if two exercises have the same general movement pattern and are hard in the same way (e.g. a legpress and a squat), expect them both to work the same.

Some extra considerations:
* If I want to do a squat or deadlift patter, and I'm not a beginner, I'm going to be using inconveniently heavy dumbells.
* If I want to train my side delts with a barbell, I got maybe one good option (upright row)

And for each individual exercise I can probably talk your ear off about nuanced improvements with one or other.

If your question is something like "If I only ever use dumbells, can I get 90% of my theoretical max gains? " I'd guess yes. Use your creativity, google, and good sense to find exercises that challenge you as you advance.

The literature is inconclusive. We have many trials comparing training to failure to leaving sy 2 reps in reserve, and meta analysis on top of that. I can for sure say the improvement, if it exists, is very small.

The upside for a beginner of not going to failure though, is that going to failure makes you much more likelly to use bad technique, hindering your hability to properly learn good technique. Every rep you do with bad technique is very counter productive.

My current model for people who already have very well established technique is: Failure maximizes growth per set, but total growth is maximized by doing more sets not to failure.