What about on iOS? And what about the fact that on MacOs notarization is more expensive than publishing to the store? I don't believe that to be a coincidence
Creating a Developer ID certificate requires a paid Apple account. Hardly free.
I think only a distribution certificate requires a paid account.
Now you've thrown me a curveball. I will have to test. I think last time I looked, Developer ID is considered a distribution certificate and requires payment.
I'll admit I haven't tried this personally, either; I've just heard that it's possible.