The stated reason was that they didn't want to make it so that appearance was tied to power upgrades as the strongest combat options were all TF based in CoC1. Never you mind the fact that CoC1 can be aced and dusted with the same nonexistent difficulty by running through as a pure human using the sword you picked up at the start of the game.
The more probable reason is that they didn't want to account for TFs that people don't write. Same reason PC manticore tails were removed and why all nonstandard TFs that aren't just "human in cosplay" aren't existent in this game. They didn't want to deal or account for them.
On the topic of the now dead manticore tail vagina
A brief refresher;
" I care about having literally unusable TFs in the game "
and then the curtain pulls back and the vast majority of TFs that do exist (what little there are) are completely functionless. Does your burning salamander tail do anything? Of course it doesn't.
Certainly a "true sequel" to CoC.