What qualifications would that be, that helped in the job as president im what way exactly? A master in not-being-an-asshole? Or a bachelor in Listening-to-experts-while-deciding-in-favor-of-all-humans? Surely the US could use a requirement of a PhD in Anti-Corruption.

That snarky list aside, what makes leaders great/very good is not learned in higher education. Yes, in some situations having a bit of knowlege can help, but it is far from the most important (additionally even with a PhD you would only be expert in one field). It is not missing education, that made people like Trump, Putin, Xi or any other of the world leaders that bad. You can even be very intelligent, smart and highly educated and still be an asshole ready to through everyone in the wood chipper to gain more money and power.

Add to that, that higher education is already more available to rich, white people (especially in the US) and you essentially excluded most people from minorities with that rule. The capitalist world is already bad enough in that regard without some education requirements.