You're right on all points. The first time around, I could understand it a bit more. When he first started running for the first time, I even got kind of excited. "A successful businessman, who isn't beholden to outside money, this could be a good change for us!" Then he started talking and it was clear he had no idea how business or government worked. All of the scandals that he'd hidden over the years started getting exposed. It very quickly became obvious that he was not fit to be in the White House. Unfortunately way too many people believed the message he was sending, and let's be honest the Democrats picked a nominee (Hillary Clinton) that was uncompelling, and just wasn't on the level to be able to compete against him. Then we got 4 years of him causing nearly irreparable damage, and that isn't even considering the piss-poor response he had to the pandemic crisis.
As to how he won a second term? Lies and fear mongering. His propaganda machine was running at maximum output and his supporters ate it up. His message was so clear and compelling that he was able to turn many of his detractors to his side. He was successful at making all of the his shortcomings that we're still dealing with today appear to have come from the current administration, even though they've been working non-stop to repair the damage he caused, and are finally starting to see things turn around. Along with all of that, he was able to split Americans into two diametrically opposed groups, for him and against him. Working together and finding common ground and compromise was made to seem impossible, and it became a self-fulfilling prophecy.
Coming from the viewpoint of a formerly communist country, I'm sure you have many parallels you can see. There are no winners in the USA today, half of them just don't realize it yet, and sadly never will.