True, maybe.
The Democrats, at least, when it became known to all that Biden was way beyond his sell by date, actually did something. There wasn't time to go through a real primary process. It would have been far better if Biden would have announced he wasn't seeking a second term, year ago, or more.
The GOP is the party that has doubled down. I won't list all of Trump's flaws, they should be known by all. The irony is that he isn't really a Republican. He just used the party for his ends. For whatever reason, very few Republicans have told the world the emperor has no clothes. Those who have have forfeited whatever political future, they might have had.
I don't see the rationale for not voting, even if the choices are not to one's liking. Certainly, one would be preferable to the other.