[DavidWoof]

> My understanding was that it was the tenant rights movement that killed SROs and boarding houses by making it practically impossible to keep them orderly

It depends on the time frame you're talking about. Long-term SROs like boarding houses were absolutely affected in the 50s/70s by tenant rights laws. But they adapted. In the 70s/80s, SROs were still widespread in large cities except that they all had occupancy time limits (usually 60s days or so) to avoid tenancy laws. But people who relied on them could just move to a new one when the time limit came, so the market was still viable.

But then in the late 80s/early 90s they all got zoned away in the way this article talks about. It was really more NIMBY than reformer. Note that this time frame corresponds with the height of the US crime wave, and what was once a sketchy urban neighbor became the source of major neighborhood blight, especially as re-urbanization started up in the late 90s