It doesn’t have to be this way. In Cata pets still had their unique trees and identity, and PvP was at an absolute peak during that expansion. 100x better pvp than Dragonflight or any of the last handful of expansions.
So the notion of this changing “in order to improve pvp” is just false.
This - there is no reason they cant still keep the family abilities exactly as they are if this was really the issue but even if secret mortal wounds turtles were a thing who cares - you have no idea how a player is specced either, why is knowing how the pet is specced suddenly game breaking?