Earlier quoted context omitted.
This has been tried before in a number of different flavors. Most leave people worse off. https://www.bloomberg.com/opinion/articles/2018-01-18/yup-re...
Thanks, I hadn't realised that obviously existing landlords might stop renting out a place, which would reduce supply of housing - that could be problematic. It also mentions that apartments got transformed into condos. This might be a problem with my not being a native speaker, but: if one apartment is turned into multiple condos, isn't it able to house more people? (Though being "new" housing, I suppose they'd then…
I could be wrong.
Relevant article: https://www.reuters.com/article/us-germany-housing/berlin-ac...