I'd argue that it's easier for a smaller affluent city of 860k to solve a problem of roughly 3,000 +/- homeless people (their problem isn't the 6k overall figure, it's a smaller subset of that), than it is to deal with 10x that homeless figure at 10x the city size. Human problems like that get more difficult with scale rather than easier.

I'm not sure how SF weather plays in to providing shelter space for the homeless as a problem. It should be easier and cheaper for SF to do it, as SF requires both less air conditioning in the warm months and less heating in the cold months. Of course, this is also where SF's terrible zoning laws show up as usual.