The survivorship bias of this movement is akin to vanlife. A lot of people burn out.
I've seen some get themselves into a poverty trap they can't get out of. Can't pay off the farm, can't make enough to survive, can't make enough to sell up and move back to the city, been out of job market too long to get a job on their old industry and would be stuck unemployed / on povo wages.
We have lots of farmland in my family that is passed down. It's a beef cattle ranch. And it's really not even that profitable even though the land is fully paid for. My grandparents farmed it their whole lives, but they also worked as teachers and now get that pension as well as social security. The farm is more of a way of life than a way to make a good living.
Note that even though the farm is worth millions, what you can income in the above plan is never more than $50,000/year.
Also, I have found that the old timers are pretty slow to change, but there is actually good reason for that. They have seen the trends come and go, some have jumped on those trends and eventually gotten burned (in my area, it was ostrich and emu farming).
Also, the slow methodical farm build-up over the years tends to evolve out a pretty efficient and effective farming method. I remember a few years ago, my brother and I got on this kick thinking there was a lot of money to be made on the farm by further fattening or "finishing" the cows before selling them. As traditionally, a lot of farms will sell yearlings to feedlots for a lower price. The feedlot then fattens them up and sells for a profit. But after a lot of research and number crunching, we found that the math just didn't work because we would have to pay to ship in the grain, since it isn't grown very locally and then we would also have to eat the higher cost of shipping those heavier cows to the auctions which are also not that close.
The old timers knew this wasn't a profitable pathway even though they didn't all necessarily know the whole story of why it isn't a profitable pathway. We have found this to be true in a lot of cases with older farmers. They know some things won't work, even if they don't fully know the details why.
Selling the dream is always more profitable than living it.
Eating your own produce means being a producer in the economy. It's not a hobby if it feeds you.