Regardless, three polls all showing Trump and Biden within single digits of each other in a rematch. They both have records as President (rare that both candidates have that) and Biden’s is the worst ever yet Trump not up by double digits in any of those polls?
First, let's throw out the old adage that most polls oversample Democrats, thus are biased by a few points in the Dem's favor. (How true that really is, I'll leave up to the polling nerds who read the internals.)
Second, you have to remember that the vast majority of people get their "news" from MSM sources and Social Media, all of which waged (and is still waging) a four-year smear campaign against Trump, with nary a bad word about Biden. Russia!, Russia!, Russia!, two impeachments, the Jan 6th hearings, etc., etc.
It's almost a miracle that Trump is up at all given all of that artificial headwind thrown against him.