By not voting, you’re abdicating your chance to vote against the destruction of the country. If a Republican wins and does what they’re promising, tens of millions of people will suffer in all sorts of ways, a full spectrum of ouch. A painbow, so to speak. COVID alone killed over a million people here when Trump was president, nevermind his disastrous impact on the country as a whole or his foreign policy (mostly because numbers are hard to come by for the Kurds and Afghanis we abandoned, but go ahead and get opinions on how the Taliban has been running the place).
If you don’t vote, the suffering and death is partially on you, because you could have tried to stop it. That’s the immoral act, regardless of how you feel about the system itself. Hold your nose if you have to, and do it.