I feel like the quote has gone over your head just a tad. The joke/quote is saying as time progresses people will continue to vote against their own best interest and eventually elect someone as moronic as the common people. And well here we are. It’s been a long time in coming yes, we’ve gone through a number of presidents who progressively did less and less in the interests of the people till we got here and elected the absolute worst person with only self interest at heart.
Sadly it wasn’t exactly wholly undemocratic. It wasn’t even what you could call close. There were attempts voter suppression and intimidation, but in the end voter apathy won out. I don’t think there’s anything dumber than choosing not to vote in such an important election, but that choice in itself was a vote.