That's because "progressive" urban politics is generally not progressive at all and dominated by the upper middle those that benefit or think they benefits from squeezing the working class out of their neighborhoods.

Those people aren’t progressives: they’re NIMBYs who learned that certain language can make it easier to get the policies they want. We have a ton of them here in DC, and you can tell by seeing what else they support: they’ll talk about affordability to block luxury apartments, flip to pretending to be staunch environmentalists to block an affordable housing project, talk about traffic or “the poor” when protesting a bike lane before pivoting to block transit projects, etc. It seems incoherent until you look at it through the lens of whether something would add competition to their future home sale or cause the city to subsidize them driving every everywhere less.

Well, building luxury housing still helps, to some degree: the richest residents of the area would buy it, and they would sell their old house to someone slightly less rich, who in turn would sell their old house… At the end of this chain you get affordable housing.

You can make $100-200k in 'easy' profit where I live by dropping the cheapest manufactured home on a plot. If you live in a place that allows it, I don't understand why people don't do it. I literally got a ~270k house for under $100k by being willing to be the guy the develops the plot. The actual house was laughably cheap, like 60k, there is a burnt out house dressed up in new paint selling next to me for like $300,000 and someone will snatch it up shortly.