Pretty sure it was rhetorical and not soliciting you for feedback. Telling a person that their genuine, curious questions are stupid is a great way to continue propping up the perception that our community is full of pedantic jerks.
Perhaps so, but many other answers premise with "not stupid," and were not similarly ostracized. I suppose some questions, rhetorical or otherwise, can only be answered one way, regardless of the truth.
Interesting how everyone ignored the point you made about the homelessness in SF.