Cloaks or capes as a costume option on the surface is fine. I would be concerned with the additional load on the servers. As these would be blowing in the wind and such.
The middle ground is to hand animate cloaks and capes to fit with the currently played animations. So it becomes part of the idle animation, or when you're walking. You can get some millage out of thi
Even if it's something Zos could somehow implement it's probably not worth the work to decide styles to work with it. I doubt it would be a small task. So, yes, if Zos could add it it's probably not
@Chrysa1is not to be rude, but this has been covered extensively. The Devs have flat out said it isn't going to happen. They tried capes while still in development and did not like the result. Sadly i