And I’m from '84 but I don’t claim the 80s because I barely remember starting Kindergarten in '89. If you honestly feel that remembering some cartoons at the end of the 90s qualifies you, I won’t deny your 90s kid membership.
Also, I hardly see this as gatekeeping. If you can’t remember the decade, I think it’s fair to say you’re not a kid of that decade.
If anything, I’d be more concerned that I still agree with my teenage self. Because that means that either you were a very prescient teen, or that your opinions haven’t matured beyond surface-level understanding.