Epistemic Status: Probably not generalisable to everyone, applies especially strong to me
It's very easy to decide to do something in the abstract on the basis that it should give you some particular skills. Here are some personal examples where I didn't get what I wanted out of my time:
These failure were basically my fault as I either just consumed the information or crammed any study I did do. Obviously I knew that this was less than ideal.
What I didn't realise was that I'd get basically nothing out of these activities. That I wouldn't be any better about talking about art, that I'd end up with only vague recollections of most of the philosophers, that I wouldn't have much more insight into psychology than someone who spent their time on Reddit, ect.
This isn't just limited to intellectual activities. I had the same experience with Salsa where I did a lot of classes, but never really put time into the basic skills. I learned more moves, but my basic skills really didn't improve.
The assumption I made in each of these cases was, "Surely doing X makes people better at Y, so I just have to do X and I'll get better at Y, maybe not as much as if I did Z, but it should still have a reasonable effect".
However, in my experience it doesn't work like that. You'll likely think it's working at the time, but any gains are unlikely to persist.
Instead, it's important to be iterative. Instead I suggest the following: Do something, see where you are improving and where you are not and then adjust. Repeat until you get the results you want.
This probably sounds stupidly obvious, but these things are easy to overlook when you are inside a situation.