First things first, we're talking about income-based public housing attribution. Not racial. Although if policies in the past means ethnic minorities have been disadvantaged all other things considered, then that will overlap, but as a consequence, not by design.

Secondly, Paris' policies are decided by the mayor of Paris and the city council, and they're elected (mayor directly, city council semi-directly). Not by "unelected bureaucrats".

Then your comment makes no sense. Policies favoring social diversity are the exact same policies that led to getthoisation? Do we agree on what getthoisation means? Because those two things are exclusive.

You say you don't want bureaucrats to put their finger on the scale of who can live in an area, that's your opinion. But if you're saying this should be purely left to supply and demand, then somewhat it is still a (non-)decision to put the finger on the scale, at one extremity, and it will have a certain outcome. Whether this outcome is good or bad will be a matter of opinion in certain cases, but not in others, e.g. what impact this has on the local economy for example, whether this leads to a more or less appeased society, and so on.