Motley Crue, along with many other bands, have announced a “Farewell Tour”, which is a tour where the band says they will play live music for the last time. However, there have been many cases where the band ends up coming back and touring again. This is similar to the Avengers movie, where many of the characters die or say goodbye at the end of the movie, but then end up coming back for the sequels.
I believe Professor X has died 4 times in the movies so far X-Men. (The Last Stand, X-Men: Dark Phoenix, Logan, Dr. Strange MoM) Can it happen for the 5th time? I guess we will just have to wait to find out.