I don't think mainstream rock music has really ever recovered from the late 90s post-grunge movement(but it could be just that digital recordings came to light during that era as well, so that was the end of the old ways). About the only decent arena-level, big rock bands still going today pre-dated the late 90s (Radiohead, Tool, Foo Fighters, etc). Outside of a small group of decent & popular bands like those I mentioned, it's all either more niche stuff that couldn't come close to thinking about filling a stadium or selling a million copies of an album, or total post-grunge crap like Nickleback, Shinedown, Coldplay, and Linkin Park(which have all had #1 rock chart hits in the last couple years).
The days of new, good rock acts that are big enough to sell out arenas are pretty much gone, and at this point I don't think they are coming back, because they've been gone for close to 20 years now. I can't think of a single new band for the past decade or so that has anywhere close to enough of a following to fill an arena.
The main problem is just that music tastes now change so rapidly. Sure there are some new artists that could sell out an arena, if it were timed perfectly within about a 3-week window when their big hit song is popular. Definitely not something that could be sustained for months on end over the course of a world tour.
Back in the day you'd hear a song from a new band, you might like it, but you weren't shelling out $15 for the whole album for one song, you'd probably tape it off the radio in poor quality if you really wanted a copy. After you heard a 2nd or third song you liked you put your money down for the whole album, and listen to it from start to finish, finding other songs you liked. It was a slow process, but a band could build a deep & loyal following over the span of many months or even years. Nobody has the patience for that anymore, in our on-demand society.