That's an assholish characterization. And when I lived in Walpole, I had Ed Markey, too. I called his office a couple of times, said, "I vote for Ed Markey, and I want <...>" and they took down what I said, and my info, and I'd a letter reply a little while later.
My current rep is Adam Smith. He has actually been less responsive than other reps I've called, but I've gotten letters from his office after calling with my requests. And in talking to office staff, you can often find out how pressured they are over issues that constituents call about. They definitely care.
Tell them you're withdrawing your support, and they'll apologize, but you're done getting listened to. They know it's a waste of time.
GOP was setting the bar low for Vance before the debate, and he easily cleared it, so with low expectations, the consensus will be that he was fantastic. Walz was no surprise, he was fine, so I think folks are going to call it a slight Vance win. It won't matter, neither got hit hard enough, it won't move anything.