American Ambers aren't anything to write home about. If we start talking about Altbier, though, my opinion differs greatly.
I do wish more breweries would make something along the lines of Odell 90 Shilling, but me and the guy you mentioned are probably the only people looking for it.
True sour beers are a niche product. There will always be those that enjoy them, but they'll never be wildly popular. The abominations being made by a lot of breweries that they call sour beers don't fit into that category, though.