Going by what general consensus shows, Joshua will beat Pulev and Fury will beat Wilder. Pulev is probably going to never fight professionally again as his age will probably not allow it and Wilder will probably not fight again if he gets beaten by Fury again because his ego will not allow him to risk a third defeat.
I don't think so, I've seen a lot of fighters who are beaten many times already but they are still fighting, of course if Wilder will lose, although he lose twice but it's just from one fighter only, and he can still fight another boxer that could still generate money for him. Boxing is more on because of money, not because of ego, or whatsoever, these guys are living a different lifestyle than the normal people, so they need money for that which they can only get when they will keep fighting. Wilder at 34 years, he still have a lot of fights left even if he lose against Fury.
The rest of your statement, I agree with it.