So, here is my idea of what shared photos, profile pictures, user cards, and backgrounds should generally be.
You can set a photo of yourself as what you'd like, but is really isn't recommended!
Some users do have photos of themselves as their profile photos, but they are far older. Personally, I think it's a bad idea.
However, what (in my opinion) is and should be allowed?
I think it is okay to show photos of, for example, your hands or feet. @AvocadoDont and I both shared photos of our hand and foot art!
This, I think, is okay because nobody could know you by your hand.
What do you guys think?