Almost not surprising. Inventors and R&D businesses patent things all the time, then it takes a while to claim them. There was a guy in Australia who apparently invented WiFi (he calls it "wiffey") and he successfully asserted his patent against WiFi manufacturers worldwide such that they paid him a couple pennies in royalties for every chip manufactured.
The saving grace is that patents only last for 20 years. After that, anyone can use the design, like Gillette's double edged safety razor (which is why their modern razors are so silly and change every few years).
The the damn resin absorbing into your skin and curing the next time you're in direct sunlight. Resin is super detailed, but I can't say I particularly enjoy doing it.
Miniatures ≠ most of the 3d printing market. Minis may be fine but the rest of the 3d printing space will be at risk and covers a great deal more use cases.
I'm not sure what qualifies as "hobbyist" in your book, but the vast majority of hobby-level printers I've interacted with over the last 5+ years are into MSLA more than FDM. 🤷🏽♂️