I do not think having an AirBNB or any BNB counts, as those are temporary arrangements similar to a hotel. They can also make good use of a property that normally would not be in use. One of my friends is a musician, she lives half of the time in Nashville, because recording studios and producers, and half of her time in Montana where she’s from. Whatever house she’s not living in at the time gets rented out as an AirBNB. I would consider that acceptable, she’s actually using both places, and when she’s not in one, she’s putting it to good use.
In my eyes a landlord is someone who sits on a property, maybe maintains it, maybe not, and makes someone else pay their bills.
I’m lucky enough to own my own place, but one of my coworkers is paying what I pay for my mortgage in rent every month, and he has less space than I do. What is his landlord doing to get a $1800 check every month? Absolutely nothing. That’s not OK. At least apartment buildings typically have amenities. Don’t get me wrong I’m still not a fan of apartment buildings, but they can be done right, they just usually aren’t.
I personally put it in the same category as a hotel. It is a necessary service for people who are traveling and need a place to sleep and relax for a week or two. Definitely not a long term thing. That is what differentiates AirBNB from renting, is you don’t expect to live at an AirBNB.