Leaving the AppStore doesn’t mean they can’t create MacOS applications. Most MacOS applications aren’t even installed via the AppStore.
So how is it “similar”?
https://developer.apple.com/developer-id/
> You can only notarize apps that you sign with a Developer ID certificate. If you use any other certificate—like a Mac App Distribution certificate, or a self-signed certificate—notarization fails
https://developer.apple.com/documentation/security/notarizin...
That similar.
Sounds like you don't use that dev account much :)