That does not seem like an alternative most people -even educated or above median IQ would favor.
I'm curious, have there been any known attempts to condition the right to vote on passing some kind of IQ, education, or rational thinking test? If so, how did they work out?
We all have to live with one another, and to make a system of government work with peaceful transitions of power, everyone must feel as if they have a voice.
High IQ, high education, high wealth, and other social advantages can be leveraged into making side-channels in the political system (e.g. lobbying), or by shaping the discussion the general electorate sees (e.g. overton window) in order to direct it towards ones goals.
Democracies have all been implemented with specific factors to make them viable in today's society, not some idealised society.
If the votes end up being noise, it comes out in the wash. And we already have protections against compelling people to vote one way or another, so carrot-sticking children for votes would (continue to be) a serious crime.
It might even grow our children into a less apathetic public.
Our laws and attitude towards "age discrimination" in this country are bizarre and flagrantly hypocritical. The ADEA forbids age discrimination, but only for those 40 or older. This would be analogous to forbidding racial discrimination, but only against some one particular race. Kind of takes away the moral high ground.