You completely misunderstood Taleb's point. In fact, you're arguing in favor of it without even noticing, but more on that at the end.
Your basic misunderstanding is that the barbell strategy is not about finding something that's completely safe; it's about dealing with our inability of estimating the real risk behind things that are presented as medium-risk investments.
With low-volatility assets, we need to use plenty of leverage for the portfolio to move at all. However, if we don't know the real volatility (and we never do, contrary to what portfolio-theory people say), it will result in a blowup. LTCM did exactly this: they over-leveraged their investments based on an incorrect model that suggested it was safe to do so and then they blew up when the market moved just a tiny bit more than their model predicted. Medium-risk investments are not always so, but we never know why, and when it turns out they weren't, it's too late and we go bust.
With risky assets, the above problem doesn't exist: we can use small leverages because we know the occasional large moves will take care of moving the portfolio just enough.
Enter the barbell. I'll stick to financial investments here but the same principle applies everywhere. While treasury bonds are clearly not 100% secure, they are as secure as we can have at the moment, so they will be our "safe" 90% of the portfolio and the remaining 10% will go to truly risky investments. Now, let's imagine a 2-fold change in the value of the risky asset; there's an equal probability for the same move up or down. If it moves down, we lose 5% of our value. If it moves up, we gain 10% of our value: this asymmetry is what the barbell is about.
Obviously, not many things double or half in value overnight, and even what does will do it rarely. So, the barbell strategy depends on as many small risky investments as possible, as the frequency of one of them go up enough would increase. (In Taleb's original case, he sold options that he thought were overpriced and, from the profits, bought options that he thought were underpriced. If the market didn't move, he made some money, if the market moved a bit, he lost some money, if the market moved a lot, he made a fortune.)
"Risky investment" doesn't have to mean "dangerous" by the way. Your example of having a bunch of foreign friends is a perfect example for the barbell strategy: you invest a known and limited amount of your "capital" (a few minutes a week of your time) in exchange for a potential, though not guaranteed, upside of unknown magnitude.
Nassim Nicholas Taleb recommends that instead of the balanced portfolio of investments recommended by portfolio theory, we follow a "barbell" strategy of putting most of our assets in a maximally safe, stable investment, and making small, sustainable bets with very high potential upside. If taken literally, this can't work because no such safe asset class exists.
Taleb typically uses US treasury bonds as an example of an extremely safe asset. This can only be true metaphorically. They are extremely safe if your measure of value is denominated in US dollars. But of what use to me are US treasury bonds in a hurricane, or if the US dollar collapses? Of what use if people like me become targets for state persecution, stripped of our financial assets or ability to access them? Of what use if I'm trying to deal with a spiritual or health problem and don't know how to find competent advice? If I'm trying to feed myself and don't know how to distinguish profit-seeking propaganda or engineered taste from genuine information about which foods are healthful?
Risks, and opportunities, are many-dimensional. And along very few dimensions is there anything like the sort of crystalline perfection of a treasury bond. A personal network extending to a variety of fields can do a lot to help you avoid getting scammed, and get access to at least an ordinary standard of competence, such as it is. A friend with different interests and skills from yours will do a lot to expand the access you have, and the skills and knowledge at your disposal. Friends from different cultures or communities can serve as an important hedge if you and people like you become a target of extraction or persecution for some reason, or simply if your way of life becomes unsustaintable.
Land you are used to occupying and know well is easier to robustly possess and develop than a rented apartment (but the upside is often higher in high-density areas, which is why young people often prefer them). A spouse makes it easier to pool assets into a venture diversified between building up a single household and seeking external trade or mercenary opportunities. And children who grow up well-adjusted to the world can be helpful if you need to navigate a changing incentive landscape when you've already committed your assets to a bunch of permanent bets (which you need to do, since time is limited). In addition, they may be a decent consolation prize if cryonics doesn't work to ensure your personal survival. Intergenerational communities of interest protect you a lot more day to day, though they themselves can have trouble reallocating resources in changing circumstances.
Risk cannot be avoided, only managed. The risk-free asset is an illusion. Someday your natural life will end, you need to invest taking that into account, and taking into account that this is true of everything else on this earth that you can put your trust in. If you allocate too much of your portfolio to "safe" assets you're leaving yourself unnecessarily exposed to the risk that this asset will become irrelevant, and failing to take the chances that are actually available to improve your position.
To a large extent, young people do well in the long run by pursuing things that are genuinely fun but not universal. This engages our natural sense of opportunity, which doesn't understand formal systems like money very well, but understands very well how to look for high-upside bets that are actually good for us. I wish someone had explained this to me fifteen years ago. If this advice helps you, then think of me when you're successful, and remember that I didn't charge you for it at the time. And remember to pay it forward.
Or, as Ecclesiastes says: