Earlier quoted context omitted.
I'm sure in some/many cases there were racial motivations but also SROs that have many unrelated people in individual rooms often become seen as flophouses and are seen as undesirable by other property owners. So they are often prohibited at least in single-family zoned areas.
Certainly, but I'll also argue that single family zoning needs to go, and upzoning enabled anywhere reasonable. Do existing owners not like flophouses? Do they not like density? Do they not like any change at all? All of the above. Property owners are entitled to their property, they are not entitled to stop efforts around them to increase housing supply or density. (as someone who has acquired lots, rezoned, and hav…
Of course they're entitled to stop efforts to change the world around them. If you moved into a neighborhood with a minimum lot size was X acres, it's a reasonable expectation that it remains as such. If someone comes along and not only wants to change that, but also build multi unit apartment complexes across the street from you, why should you not have a say? Clearly the person was not allowed to do that before changing the zoning rules so why can't I try to stop them from changing them at all?
There's nothing racist about wanting to live a quiet suburban or rural life where you can neither see nor hear the next house over.