[sakagami0]

A goal was you can treat it Exactly like an "Interface". I agree it looks totally nonsensical but I think of it as a text replacement.

[eyelidlessness]

The assignment to class properties reminds me an awful lot of stuff I've seen in Python, particularly in Django/REST Framework.

But the class wrapping thing would just break my brain every time I tried to use it. Calling plain functions just feels a lot more natural to me.