Again, I agree with what you’re saying in principle, but how do you propose to draw that line now?

There will never be a perfect time to draw the line, because the DNC will always play chicken with its own base as long as that continues to get them elected, they will always be putting us in that position of choosing between their fascist lite pick and the gop's fascist. The only weapon we have that they care about is our ability to deny them power. They don't care about protests, they don't care about articles and letters, debate or polls or anything, as we see none of that changes their behaviour. They care about money and access to power.

So, the solution is to starve them until they realize the party simply can't sustain itself on non-existent maga swing voters. It can't leech enough "moderate" conservatives to survive. They need to be brought to the understanding that their route to power is not to be Alt Republican, it's to be progressive and anti-fascist.

People can say the DNC won't care and it will never work that way, but we've seen a real example from history that starving parties works. When Republican support was waning in the 1950s and 60s, the Republicans went out hunting for a new demographic to sustain them. That's what the Southern Strategy was. Granted they were going in the opposite direction, but the Democrats can be put in the same position and since the GOP already occupies all the white racist territory, Dems have very few other places to hide from Millenials and GenZ.

And in the meantime those groups need to keep voting and keep fighting to get progressives in every position they can. They just need to be disciplined about not backing corporate candidates, they need to be unelectable.

And yes, I understand this would likely mean some really shitty years, but that's the cost to make Democrats understand they need their base.