I think SRO's are very different from "One bedrooms" and even from studios? a studio or a one bedroom has a kitchen, a bathroom, and some living space... I think SRO's typically have a bed, a chair, and sometimes a desk. Bathrooms were shared, I'm not sure how kitchen/cooking space worked?

yep, a ton of SROs have been lost in cities like SF https://ccsroc.net/s-r-o-hotels-in-san-francisco/

also - gentrification of apartment housing stock over time raising the price floor and phasing out of public housing