I guess I don’t often touch metaclass either, although after reading this article it gave me some ideas on how I might better implement object validation patterns. That being said, I also have recently become acquainted with pydantic, which does take care of some of that.
Pydantic’s a great example of a good use of metaclasses. I’ve seen them abused in places where there were far simpler ways to accomplish the same goal, and promptly ripped that code out.