If you are a citizen, subject to the laws and the taxes, you should get a vote: no exceptions.
Why? To what end?
I am certain, because you use IQ as a metric for who you think should vote, that you are smart enough to puzzle out a steelman argument for my position.
Use that big brain of yours and try it, you might learn something about humanity (and humility)!
There’s lots of potential reasons. I’m trying to figure out which one you’re invoking?