Yes, voting for the party and candidates that I want to vote for based on my own convictions - which right now doesn't include any national Democratic candidates.
Sure sounds nice on paper, but what do you expect to achieve by doing this?
What do you think would happen if everyone who is disillusioned with Biden but isn’t a Trump supporter voted 3rd party?
Maybe they’d learn their lesson. But if instead a non-negligible fraction don’t vote for Biden, he’ll likely still lose and the DNC definitely won’t learn their lesson.
But whether or not the DNC “learns their lesson” may be a moot point: the goals of the Republican Party include eroding the civil rights of LGBT, immigrants, and women, as well as dismantling our democracy in general. This is not coming from DNC propaganda, this is coming directly from the mouths of republicans, as well as examining their actions on all of these topics while Trump was in office.
I don’t expect Biden to make anything better. I do expect Trump to really, tangibly make things a lot worse. Again, this is no “what if”, Trump was president and did make things worse, and he and other republicans have stated their goals for next time.
As for making actual progress, if Biden wins this election, especially if he wins by a significant margin, then the Republican Party might rethink their strategy, which would lead to a much healthier election in the future. Additionally, after this election (if Biden wins) he won’t be able to run again and the DNC will have to pick some form of fresh blood. That’s a far better opportunity to actually work on improving the system.