If someone's a bad amateur innkeeper, what's the worst that could happen? Their guests might have a poor experience, or at worst get bedbugs or something (which happens commonly at real hotels a lot these days anyway). At the very worst, their "inn" could burn down, but that's a risk with any building, including whatever home the guests normally live in.

Amateurs flying aircraft have the potential to cause far more havoc than this, or even the havoc that a bad driver could cause.

No smoke alarms is an obvious issue in my experience.

The better of the amateurs are as good as professionals.

I’ve been very well-taken care of in AirBnb’s, and I’ve been driven around well in Ubers.

I don’t think their concern is the ceiling of any of those domains, but the floor.