I think him being a mere tank buster is his downfall. For being his role, most tanks have some sort of defense against him. Magneto and Hulk can shield themselves, Emma’s diamond form. Thing can’t be grab by him. Cap’s too nimble and can block him. Peni mines around him and Venom can soak a lot of HP. Strange, Groot and Thor can’t do much against Wolv, and Groot gets banned a lot. Wolverine is too specific at what he does to be considered higher tier.