The really interesting news here is that in Turkey you need a degree to run for president.
United States from the 1890s to the 1960s required voters to pass a literacy before they could vote. We should bring back this rule. Voters should have a minimum level of knowledge about the world, science and democracy in order to vote. This would have prevented the current disaster which threatens not just our democracy, but by denying climate change, the entire planet.
A literacy/civics/logic/knowledge/etc. requirement would at best discriminate against people who are uninformed, unintelligent, uneducated, unable or unwilling to take a written test, etc. But they are people whom the laws affect and who should be able to vote. I don't think that they are a comparable category to the exceptions mentioned above, but that's debatable.
Most importantly, the test would be optimized to exclude whoever the test designers and proctors consider, knowingly or not, unworthy.
I understand the desire to exclude the dummies. I know thoughtful and educated people who espouse the same wish, but it's just too dangerous.