And you think if everybody would buy their own houses, that wouldn't be the case? Like the poor artists who made Berlin famous, who thrived when there was an endless supply of living space (because of the wall and other issues), they would just have bought their own places and gentrification would have been staved off forever?

Are you sure it is not the other way round: increasing attractiveness of the city (change of character) has lead to increased housing costs?

70% of Germans rent. Any increase in rents is broadly felt, especially compared to America, where most political power in most cities resides with homeowners (~63% of the population).

https://www.bloomberg.com/news/articles/2019-04-13/berlin-ho...

Increases in rent are driven more by people wanting to rent in a given area (typically driven by jobs) than by an owner or landlord selling a house to a different landlord. Rental demand is much more variable over time than the change in supply from marginal landlords buying existing properties.

If prices are rising, people are crying because they are not home owners. If they are falling, people are crying because they are homeowners. Weren't a lot of people in the US screwed when the last housing bubble burst (2008)?