Actually Trump "only" got 304 Electoral College votes in 2016, and called that historic and a landslide (it was neither), so Biden's victory is bigger.
Trump might have received slightly less number of Electoral College votes compared to what Biden received in 2020, but the fact remains that he won most of the states with a larger margin. During this time, Biden won 3 states with margins of 20,000 or less (Arizona, Georgia and Wisconsin). Back in 2016, Trump had a margin of less than 20K only in the state of Michigan.