IMHO, tubeless is a personal thing. It has advantages for some people. When I bought my most recent bike, it was tubeless ready. I really considered going tubeless because it's the latest & greatest thing. I weighed my options, did a few hours of ready, and decided tubeless wasn't for me. The self healing concept is an advantage for people who ride in places that cause regular flats. As you pointed out, the lower pressure is also an advantage for some people, but not me. For some people, replacing sealant every several months is a small price to pay for no flats. For those of us who don't have flats, it becomes a hassle.
FWIW, another option for people who experience regular flats is to get a tube with a removable valve core & ad some slime. After 2+ years, when the slime dries out, just replace the tube without any mess.