Promoters should be making competitive HW matchups

[The Hammer]

Tyson Fury Dec 1
Bryant Jennings Dec 8
Mike Perez Nov 17
Ruslan Chagaev Dec 1
Denis Boytsov Dec 22
Steve Cunningham ?
Deontay Wilder ?
Carlos Takam ?
Eddie Chambers ?
Edmund Gerber ?
Manuel Charr ?
and many others

are looking for an opponent for their next fight.

Why don't they just fight each other?