We are currently at a time when the P4P debate is wide open. A clear P4P #1 is not so easy to define in my opinion. By my rough of the top count you could make an argument for at least 6 - 7 guys being able to make a case as the #1 guy.

In no particular order:
Loma
Crawford
Usyk
GGG
Mikey
Inoue
Wangek

There are others to like Spence for example who could be only 1 big win away from ending that bracket.