The notion that Biden represents a lesser evil compared to the chaotic reign of Trump is a common argument. However, we must not forget that there exists a moral threshold below which neither choice is acceptable. To suggest that enabling a literal genocide can be considered a lesser evil is a morally bankrupt stance.
Saying that voting for Biden is a moral obligation to prevent the return of Trump perpetuates a dangerous fallacy. It implies that the democratic party is immune from scrutiny and accountability, no matter the atrocities they commit. This line of thinking allows for a never-ending cycle of justification, as long as there's somebody considered worse, the democrats are granted a blank check. This is nothing more than a form of gaslighting, manipulating the public into believing that their only choice is between two evils, rather than demanding a better standard of leadership and true representation.
This would be my response:
Biden and the DNC need to do more to prevent another Trump presidency.
They ran Hillary despite her being deeply unpopular. They almost ran her on a "It's Her Turn" campaign.
As far as I'm concerned they let Trump win.
And now they're doing it again while scolding people because they are convinced of the notion that Democratic Party cannot fail, it can only be failed and that they are entitled to votes rather than showing a true commitment to representative democracy by literally representing the politics that is most popular based on a democratic consensus.
They are a parody of liberal democracy.
Demanding that people hold their nose and vote didn't work the last time Trump was elected. Instead of yelling at people to vote against their interests, you should be yelling at the Democratic Party to start representing the people's interests.
(I would possibly throw in a jab about how they might be a rank political opportunist of such a degree that they can vote on the basis of someone who they do not believe in and have zero faith in but you need more than that.
Elsewhere I have outlined an argument to get them to discuss how Biden hasn't been able to address any of your concerns, in as much detail as they are willing to go into, before telling them that you have no faith in Biden and you cannot in good conscience vote for him because they have just convinced you that he is completely incapable of achieving anything and this would mean voting for him would be throwing your vote away - it's very hard for someone to backpedal after they've just spent the last 15+ minutes excusing all of Biden's inaction, even moreso when you understand that the only way they can about-face is by implicitly arguing that Biden can in fact achieve change for the things that are important to you but he simply chooses not to act.)
Don't forget about the pied piper strategy!
how does that work?
it was Hillary's strategy in collusion with corporate media to elevate the most extreme GOP candidates (Trump, Cruz, Cain iirc) so that the nominee would be easier to defeat in the general. and it worked out great