My kids say I don't have a good grasp of how popular bands are, but I think most of these are popular? I have seen Jason Isbell, Sylvan Esso, and Bleachers in pretty big venues here.
I was thinking about "mainstream", but that could be interpreted a few ways. I think these are popular bands within their niche genres, but I don't know if I'd call them mainstream. If I'd ask most of my friends about Sylvan esso maybe one out of ten might have heard of them. But if I talk to someone that listens to a lot of electronic music they definitely would know of them. Sorry @OP: I might have misinterpreted your prompt!