Harris saw a 6M vote undercount relative to Biden. You can argue all the reasons why, but you can't deny Democrats would have won if they'd been as popular in 2020 as they were in 2024.
It's bizarre to see people insist this collapse in support has nothing to do with the policies of the party people stopped liking.
In the same vein, there's a real hard November coming for the GOP this year. Their incompetence is going to cost them.