Different versions of the same subclasses

My new DND group has been having access to more 3rd party content than I'm used to. Some of it included the Kobold Press versions of the Witch and Necromancer as separate classes with tons of subclasses.

However, I spend a lot of time on DND youtube and know that Pointy Hat has made, published and sells his own versions of the Witch and Necromancer. And I just... is this plagiarism? Is the hat canceled? Or is this something that anyone can do with third party stuff?

It's not "plagiarism" to create your own D&D subclass that has a similar concept to someone else's. If the actual text of the book were copied, then that would certainly be plagiarism, but neither of these publishers can make any kind of claim on having originated the ideas of witches and necromancers.

There are tons of third-party and homebrew classes and subclasses with similar concepts to others that already exist. It's definitely not worth getting up in arms about.

Kobold Press, Pointy Hat, and Mage Hand Press all have their own versions of witches and necromancers, but each have their own unique ideas and associations.

Additionally, the idea of necromancers and witches date back centuries and possibly even millennia, and Witches and Necromancers are pretty common archetypes in modern tabletop/video games. Saying that everyone who made a necromancer or witch is plagiarising from these original ancient ideas would be stupid, so why say it about third party content?