Resource packs that contain a "player.entity.json" file revert all skins to Steve and make capes invisible

When a person activates any resource pack that changes a player's animation, if it doesn't change the model, the animation usually breaks, or reverts to vanilla. I've tested it with 3 packs, all revert to Steve as the player skin, no matter what, meaning all skins appear as Steve, and only an old, slightly broken one that put in elbows and knees to the player didn't have the animations break in any way.
While resource packs in general causing bugs may not be supported in this, this is caused by any change to animation to  the player in any way, not any specific pack.

Steps to reproduce

1. turn on a world, or go into one with a player animation changing resource pack
2. enter the world
3. view the player, arms paper doll, or 3rd person model

What is expected: the player's skin is preserved, and the animations do not break

What is observed: the player's skin, whether classic or made in the character creator reverts to steve, rarely with slightly glitchy textures.

If screenshots are wanted, I can take some and provide them.