that's before you even look at medically-related and late age cognitive decline, but unfortunately there are massive socio-economic effects that work against this
More than socio-economic, the chief factor that advances US political candidates is, simply, fame. These days fame is achieved by somehow becoming an outlier: loud extremism, incessant self promotion, and spending truly insane amounts of money. Intelligence of any kind is irrelevant.
Yeah. The right hasn't been able to repeat Trump, other candidates following his playbook have usually failed. And I think it's because they don't have his three-plus decades of lowest common denominator fame and enough money to buy himself out of repeated business failure and corruption. It's a perfect storm.
