I'm Canadian. I've paid attention to US Politics since 2008. Donald Trump is the worst US President ever, PERIOD.
You're not wrong.
"Donald Trump is rated the worst president in American history by a group of 170 political science scholars."*
Even ranks as one of the worst presidents by his own right-leaning political scientists. Mind you, this was pre-COVID so he would rank even worse now...were there any lower to go.
"But even among the Republican scholars, Trump ranked very unfavorably. Respondents who identified as Republicans or conservatives ranked Trump 40th out of 44 presidents. Self-described Democrats and Independents both ranked Trump dead last."*