If you have the WBC belt and fight the WBC Emeritus Champion, what belt do you think is on the line? WBA? IBO? IBF? Or could it be the WBC?
Peter was never in talks to face Wlad in a undisputed fight. Sure , he said he'd beat Wlad after he beat Vitali , but that doesn't make him a greater WBC Champ than Wilder.
Peter has the better resume than Wilder, better top wins anyway. Also Peter would be undefeated too if he had fought the comp that Wilder has.
IBO, World Champ IBF World Champ WBO. World Camp WBA World Champ WBC World Champ As someone recently asked- "Exactly how many worlds are there?"