[GBV]

Arena Bands are going to be a thing of the past.

I think every generation will have their own arena bands. First "new" band that comes to mind as an arena band (that will probably last for a while) is Coldplay. I'm sure I could come up with others.

sure, there will never be none. but even back in the 80s you could rhyme off 20 bands that could sell out arenas year after year, album after album.
(and most the current ones that still can are 80s bands or prior...i.e. bon jovi, aerosmith, acdc, metallica etc)