I have been running 19.5's, for several years. I also have a 4x4 Samurai I run off road. I played with Sandrails, Baja Bugs and Dune Buggies for years. While I agree, you can get more places with a bigger footprint, I have seen too many people get obsessed with it.
In all the years I have played off road, mud or sand, the only time I have had a flat was when I followed someones advice on airing down to the point of being too low. Different applications have different requirements. When we frequented Pismo Beach, it was in a 2WD vehicle, and never aired down. Never had a problem. Fair to say, do not drive out into the dunes, stay close to the ocean.
I have been on the Rubicon Trail with a group of wheelers, most with 34 to 40 inch tires almost flat, and have one of them tell me 30 inch tires are to small on my Samurai and I should let more air out of the tires. I point out, they may recall I just came on the same trail as they did, traveling with them. Maybe they should have smaller tires with more air.
To be fair, if I frequently ran in the desert off road I would rethink my tires. Probably would go with something like Jefe is running. I would also get a smaller TC, and 4x4 truck.