Many people who don’t vote believe (with some pretty good justification, imo) that it’s all bread and circuses, that ultimately the U.S. government is going to do what it wants regardless of who gets elected. I’m personally with you that it does make a difference, but I don’t think anyone’s done a good job of making a case to the skeptics that things would have been substantially different if Kamala Harris had won (and pointing out how shockingly awful things under Trump are isn’t enough, especially considering how many moderate Democrats have been happy to go along with that awfulness when push comes to shove). How do you convince people they still have a modicum of power in a system that is so clearly designed to make most of us powerless?
That’s the whole problem. Democrats see the very understandable cynicism many people have around their vote actually mattering in our current political reality, and they conclude it’s because they’re stupid or misinformed.