/tp on mannequins doesn't handle rotation right

/summon mannequin ^ ^ ^3 {NoAI:True}
/tp @n[type=mannequin] ^ ^ ^4 90 0

I would expect to see the mannequin move and rotate to face west. In fact the body only partially rotates, though the head seems to be right. The body doesn’t line up.

I use NoAI here, so I can say the following: Change “mannequin” in the above commands to (say) “villager” or “cat” and it will behave the way I expect. (That’s why I expect it.) (Without NoAI the mobs own movement will cover all this up.) I can also push the mannequin around on the ground, which I can’t do with the villager or cat.

If you summon an armor_stand, it will also work as I describe, and it is not a mob.

I also use NoAI here to demonstrate the following related problem: If the mannequin arrives above the ground it will fall. The villager or cat will not, NoAI prevents it. This is another way in which mannequins do not act like most entities. I believe the problem has something to do with the categorization / initialization of the mannequin entity type, where it does not use what other entities use for these settings. (The armor stand will also fall, though NoGravity fixes that, as it does for mannequin, but I can’t push it around, of course.)

Consistency is not a special feature request, it is basic to the functioning of a system. If each mob behaved its own special way on /tp rotation, that would be really hard to use, and it would get fixed. The fact that this is one entity acting differently makes this equally a bug report, not a feature request.

I expect the mannequin to act either like a mob or an armor_stand, not in a different way from either, when it comes to gravity, rotation, and other basics.