I don't think that's the case. The parent's opinion lines up pretty well with what I observe in San Francisco. Our mayor calls herself a Democrat, but most of the policies she pushes feel pretty conservative to me. The Board of Supervisors (our "city council", which has quite a lot of power) is all over the place, but definitely has what I'd consider a conservative element... but of course they still call themselves "Democrats", "progressive", "liberal", whatever.

I can't speak to the opposite phenomenon, where places controlled by Republicans tend to have quite a few "liberal" Republicans, but it seems plausible that would be the case as well.

It’s possible that you just have an extremely left-wing view of what it means to be progressive, such that people who identify a s progressive to you and who would be called progressive by most Americans appear conservative to you. This is definitely the case with Republicans who call an insufficiently conservative Republican a “RINO” or “Republican In Name Only” (although the Trump wing which isn’t conservative has colored it to refer to Republicans which aren’t sufficiently extremist).

It’s also possible that SF tried more progressive policies, but found they didn’t work in certain cases (for example, the recent DA recall). Note that I’m not trying to litigate whether conservative policies would work better than progressive policies or any such thing.