The moral difference between BlackStone and the random NIMBY homeowner is that the homeowner exerts control over the planning process while Private Equity just piggybacks on the homeowner efforts.
[1]: https://missionlocal.org/2018/06/the-strange-and-terrible-sa...
[2]: https://sfyimby.com/2022/05/san-franciscos-historic-laundrom...
Of course, the tone of thse first article makes the problem even more obvious, in a black comedy kind of way, with the writer complaining about "luxury prices" of the resulting apartments without considering even for a second why the prices might be so high.