It’s funny, you know, because Coldplay is probably one of the only few potential collaborators out there that the entire fandom can get on board with.
Even someone as true a friend to BTS as Halsey got backlash from certain parts of the fandom, not to mention Nicki, Charlie Puth (for good reason), Jason Derulo, Justin Bieber, even MAX at some point and to a certain extent, even Ariana.
Cause Coldplay are one of the contemporary rock legends and true musicians with proper cred and rep. You would be hard pressed to find someone who does not like Coldplay. A collab with Coldplay was not even something I ever thought in my wildest dreams but in case it happens, I do feel that it was probably planned way in advance and the Fix You cover was supposed to be the first big hint towards it.