Yeah, poorer people can be elitist, but that doesn't necessarily make what McMansionHell is doing some elitist sort of enterprise. It's a guy/girl pointing out architectural flaws in buildings and discussing why they are flaws. It's as elitist as movie critic talking about a new film, and in that sense it's ridiculous that the site is being pulled down over this. You aren't entitled to have somebody agree with your taste.
Edit: You're right, nobody is arguing that it was pulled down for that and I didn't realize until I read a bit more. My point about entitlement still stands though.