These are all the reasons I wear capes!
Everybody knows and loves Spock's cunty black cape from Return of the Archons. While the rest of the crew's disguises are more or less congruent with each other and with the planet's natives, Spock is the only caped bitch on the entire fucking planet as far as we can see. There are other, more fitting, in-universe ways to cover his ears. He had no right to be serving this much cunt with this look.
So the question I usually see is: Did Spock pick this look for himself? And is he this weird because he's a Vulcan? Or is he, individually, just this extra? Here is the secret third thing: This cape is the PERFECT accessory for an autistic person.
Feeling overstimulated? Raise the hood; it works like blinders on a horse.
Feeling understimulated? It swishes around like a princess dress when you move. Spinning optional.
It's not as tight around the body as a jacket, so it keeps you warm without having to feel a structured jacket all over you while you're trying to go about your day. Meanwhile, the part around the top of the head is just structured enough that it's not touching your face or falling off all the time.
It's a good conversation starter. If you want people to talk to you but you don't know what to say, this cape is guaranteed to get their attention and get the conversation going.
Have issues around being perceived? This one is a little harder to understand; but when you have a cape like this, people notice the cape instead of noticing you. There is a freedom in it. It's why a lot of autistic people are into cosplay.
Also, it helps with that "why are they staring at me" anxiety. They are staring because I am beautiful and mysterious and elegant and wearing a fucking cape.
In conclusion, I really hope Spock kept this cape and wore it on other occasions that we don't see on-screen. Also, I will be buying one for myself in the near future.