Maybe he’s from a doofus reality making him still the smartest

Isn't doofus jerry smarter? Like at least smarter than doofus rick?

Maybe he used to be a “regular” Rick and something happened to him (I think I read someone suggest he might be a Rick who used Needful’s microscope)?

IIRC Doofus Rick doesn’t even seem that “dumb”, he actually seems pretty emotionally intelligent in a way most Ricks aren’t, going off of his read of Jerry’s collector coins. Maybe he’s just “smart” on a different axis and that combined with being a Rick was enough to put him in bounds of the Curve.

I would argue that he is the smartest person of his dimension even with Doofus Jerry because while Jerry conquered their world, he had no way to make portal travel whereas Doofus Rick could.

The only two ricks that made portal travel are C137 and Rick Prime. Everyone else accepted rick prime's deal and had it handed to them