I know plenty of YIYBY advocates who live in wealthy parts of SF that have clean streets, no homeless and own large properties. a good example would be 'democratic socialist' district 5 supervisor Dean Preston https://twitter.com/DeanPreston
Preston talks all about progressive housing on Twitter all the time, so does heroin Haney. Neither of them can get it together to practice what they preach so it's all useless YIYBY performative posturing anyway. In the past SF has wound up building disasters like Geneva Towers based on somewhat similar utopian ideals
The language he uses makes him a left-NIMBY, but that’s just what they look like in cities. Found in NYC too. In suburbs the same people switch to talking about property values and 50s rural neighborhood character.
Dean Preston is one of the most virulently anti-YIMBY politicians out there. He is constantly lying about YIMBY positions and starting fights over nonsense on Twitter.
You and he agree 100% on building new apartments, Preston hates them, and as a rich man living in a very expensive single family home in one of the most expensive cities in the world, he fits right into the NIMBY mould.
However, Preston also believes that homeless people should still be treated like people, a position he shares with YIMBYs. Due to that commonality, but also having irrational hate for YIMBYs, he is sometimes called anti-YIMBY rather than NIMBY.