Capes always tilt to the side slightly when moving and riding entities

The Bug:

Capes always tilt to the side slightly when moving and riding entities.

Steps to Reproduce:

1. Ensure that you have a cape enabled and summon a horse by using the command provided below.

   /summon minecraft:horse ~ ~ ~ {Tame:1b,SaddleItem:{id:"minecraft:saddle",Count:1b}}

2. Mount the horse, begin moving with it, switch to third person, and watch your cape closely.
3. Take note as to whether or not capes always tilt to the side slightly when moving and riding entities.

Observed Behavior:

Capes always tilt to the side slightly.

Expected Behavior:

Capes would not tilt and would be straight.