Your (and many) arguments about AirBnB revolve around housing, economics, etc.

There are other arguments to be made about the quality of service & safety. Read some of the comments from another recent HN story: https://news.ycombinator.com/item?id=10291070

My own individual and anecdotal story: as an individual whose neighbor was AirBnB-ing his apt next door to mine, seeing dozens of unfamiliar faces (and, without going into detail, the behavior and antics of some of these occupants) did not make me feel safe. If anything, they should severely restricted under this guise, not "affordable housing". (Though I do agree that more housing would generally improve the situation for all).