Trump was actually down in all the polls in 2020 anywhere from 4.5 to 10%. RCP average Biden was up 7%.
https://www.realclearpolitics.com/epolls/2020/president/us/general_election_trump_vs_biden-6247.html
The tide is turning.
Trump was never down in the polls. You cant draw crowds as large as he did out of office and honestly believe he was down.