They aren't wrong. At least not in spirit. In a non-stupid system they'd be correct at every level.
Https://youtu.be/s7tWHJfhiyo
Until everybody in the conversation understands the contents of that video, you aren't at the point where you can have the conversation meaningfully. It changes the whole game.
And once they understand it, the remaining conversation may just be a mutual nod of understanding. First past the post is a third party killer, and not because the idiot populace lacks the will. The actual voting math itself is the problem, and ranked choice (or similar) solves the voting math problem in a way that third, fourth, fifth parties can exist and win, instead of debuffing allies and by so doing helping their enemies.