Firstly, I agree that skipping health insurance in the U.S. is dangerous. Like others who have posted here, I have had personal and relatives/friends experience with unexpected large medical expenses in otherwise healthy people. An additional factor which folks outside the U.S. are probably not aware of is that insurance companies here have negotiated rates for medical expenses that you don't get as a private individual. Thus, for say a dislocated kneecap, for imaging, doctors visits, physical therapy, etc. the medical system may bill $20,000, but if all the work is "in network" the insurance company may only have to pay $5000. If you don't have insurance, the medical system will want the full $20k. Sometimes they will negotiate lower rates with you on a case-by-case basis, but you can't count on it, and it will take a lot of time and arguing. To be fair to him, I don't think he said everyone should do that, it is just a risk he is willing to take.
The other thing he recommends that I'm wary of is some of the more difficult/dangerous contracting work he does on his own home. While I wouldn't mind knowing how to replace my own roof in a theoretical sense, I would rather not do it. I have one friend who died falling off a roof doing his own work, and another (a contractor) who broke an arm doing a roof replacement. I would rather pay someone to replace the roof, and instead learn to do my own taxes, which will pay "dividends" every year for my entire life, won't get me injured, and which he outsources.
Part of how I approach the "do it yourself" versus "outsource" is how many times I will need to do it. I've had pros do my taxes a few times when it was more complex, and I was dealing with things I wouldn't need to do often, and I studied their results to make sure I wasn't missing anything when doing it myself. I may need a new roof twice in my life, I'll pay someone for it, and I expect a warrantee with the work. I'll need to replace a lot of outlets and light fixtures in places I live, and in my previous work I worked with up to 440V/30A circuits, so I'm comfortable doing that myself. For some small jobs, its actually more of a pain to find someone to do it than do it yourself.