I don't think there's really a single thing I read that led me to this. I'll list off life experiences that come to mind, though:
(1) I guess it probably started off back in 2015 when I read about Utah's "Housing First" approach to ending homelessness which got quite a bit of national news coverage at the time[0].
(2) I started talking to some of the people experiencing homelessness who hung around the grocery stores I went to in Seattle, seeing them as a person and not an unsightly problem to be swept under a rug. Ask them what food they want then buy it for them sometime, you might get a good conversation out of it; if they're not up to talking, well, someone got a meal out of it at least - and they shouldn't really owe you anything.
(3) Then one year I went on a business trip to Copenhagen, and saw their hybrid system of both privately-owned & socialized housing; went to a BBQ at a coworker's place at one of the socialized housing complexes, which was very nice.
(4) I bought a condo myself, and cheered as the price went up on Zillow. Then was struck with the somehow extremely obvious yet little-noticed contradiction that house prices appreciating in value, which is more-or-less the driving thesis of investment the largest asset class in the world, is diametrically opposed to the goal of making housing affordable - as in, cost less & thus be worth less!
(5) I met my current partner, who is a medical resident in combined internal medicine & psychiatry. Their patient population is almost all homeless. I heard many of their patients' stories and the misery they experience.
(6) I started watching some urban planning videos by donoteat01 on youtube[1], who is an entertaining presenter that uses Cities: Skylines to illustrate common concepts. I especially liked their video on gentrification[2].
(6) Somehow I heard about the Tax Amazon movement in Seattle[3], which aims to put a payroll tax on workers at large corps & use the proceeds to fund the creation of public housing. I thought - that sounds great! Even though I work at a large tech corp myself, I'll participate. Speaking with people at the various planning meetings (who were almost all outside the bubble of friends-who-work-in-tech I had) was really educating and solidified my views on all this.
Sorry that isn't a link, but more a story of how I arrived here. Hopefully it helps you in some way.
[0] https://www.npr.org/2015/12/10/459100751/utah-reduced-chroni...
[1] https://www.youtube.com/user/donoteat01/videos
[2] https://www.youtube.com/watch?v=LdeirDrinWk
[3] https://www.taxamazon.net/