No, there aren't too many.
Per @benroyce's post, all that’s needed is to make sure that non-voters actually show up to the polls and cast for Ds. If everyone who voted for Biden had voted for Harris, she'd have won easily.
(Graphic shows U.S. presidential election results 1976 - 2024 ranked per percentage of eligible voters. In every year except 2020, proportion of “did not vote” is higher than for any candidate.)