If Trump wins, he will outright ban the Democratic Party, if not at least make it SUPREMELY difficult for the party to be changed in any significant way for the better. I will only vote for Biden to buy a little more time in which for the more progressive wings of the Democratic Party to act. Technically, there's nothing stopping our government from just Thanos snapping a party out of existence. I really would not want to see Trump snap his fingers and suddenly the only party with the means to oppose him just stops existing. And before you say the DNC doesn't have the means to oppose Trump and the GOP, they absolutely do have the means. They have all the tools they need to stop them. The will to use those tools? That's what the DNC is sorely lacking. This is because the party is suffused with neoliberals and their bullshit that MUST be called out and pushed out. Unfortunately these neolibs also have a lot of money, something something the more progressive members of the Party are lacking.