I saw Beauty and the Beast on my last trip to WDW and was pleasantly surprised by how wonderful it was. I'd be disappointed if it's gone when I get back there someday.
As I recall, it was simply on a stage. I don't see why the theater has to be "either-or" when it comes to shows. Surely there could be a way to put on both productions. They could alternate on the day of the week. Or one could have the early showings of the day and the other the latter showings. Do they really need to get rid of BATB?