Mycology

Just because you dislike two things, you don't have to lump them under the same definition. Language could evolve to consider registration-required sites to have a paywall, but that would be stupid and counter to similar usages of "pay". People seem really eager to stretch negative definitions to include other things they dislike, but it's not the word that makes something bad, it's the thing itself. Two things can be different/distinct concepts and also be equally bad.