I'm in Puerto Escondido right now. There are a lot of
boats doing exactly that, and the
Sea of Cortez is riddled with coves and towns that you could effectively live in for as long as you like. A lot of people have been on the peninsula (as in sailing / living aboard) for >20 years.
You can also hop across the Sea (1-3 day trip, depending) and end up in a huge town like Mazatlan. Hop back across and you can be in a 50 person
fishing village.
It's a beautiful place but not my cup of tea long term. Some love it, and that's good for them. Beautiful scenery, amazing
fishing, the best
hurricane refuges on the western coast of Mexico. But it is dreadfully hot in the summer, it's quite expensive, and if you can imagine the type of person that would spend twenty years in a desert... well... they can be a little set in their ways.