To expand, not arguing against anything you mentioned:
People want perfect solutions, and that's what makes it complicated. Ending homelessness is easy, but people also want to end hunger, and sickness, and poverty, and... so proven solutions for homelessness get branded (by the affluent, as you mentioned) as "half measures" and nobody supports it.
And I've seen this play out IRL in casual intoxicated philosophical conversations with friends too, so I don't think it's a good faith/bad faith thing. I feel like they get bogged down with it as an optimization problem, where I don't see a problem with knocking together good enough and improving later.