I think the view that we “just need more market-rate housing” is simplistic. Blindly building lots of housing doesn’t necessarily mean that people are going to move there. In Boston, for example, many of the luxury condos that have been built are being used as investment properties:

https://ips-dc.org/report-towering-excess/

I think the 61% of people who want affordable housing and homeless housing recognize these failures, which is why they want a more direct solution.