As they say in the investment community, past performance is no indicator of future performance. Previous administrations were nothing like Trump's. So a Biden administration that simply returns America to normalcy could be extremely popular, for independents and even for many conservative Republicans. Conservatives want this kind of normalcy, and Trump's term was anything but "normal".
In fact, if you compare the past 40 years of presidential terms to Trump's, Democratic and Republican administrations were much more alike than Trump's administration.