You're asking the wrong questions.

The bigger issue is that the US system of voting is set up so that:

1: Most elections predictably go to one party or another.

2: Most representatives are chosen by small minorities who vote in primaries.

The Presidential election is almost always close to 50-50, and due to peculiarities in how it works, is chosen by small regions. Basically, Google "Electoral College." Essentially, most states will always predictably elect a Republican or Democrat, so the election is chosen by states that are hard to predict. (For example, if you live in a state that always votes for the Republican candidate, trying to convince people in your state to vote Democrat won't make a difference because all of your states votes will always go to the Republican.)

Furthermore, because American news is always very critical of current leaders, if a president holds power for 8 years, people will always want change and always vote for the other party. It has little to do with the merits of the current President. People who hate Trump will hate everything he does, even when he does good things. People who hate Biden will hate everything he does, even when he does good things.

I've heard Poland has similar issues, FWIW.