As long as those trusting their money and their lives with these concepts are aware of the risks, no issue.
Unfortunately, everything I’ve seen so far is worthy of a bad late night infomercial…though they’re apparently catching enough venture capitalists drunk-dialing after last call.
…while the rest of us not so well funded participants in the national airspace system and residential property owners hang on for the loopy regulatory mess that’s going to accommodate these visions of utopia.