Additionally, I'm just curious what you have at stake in this argument. It seems sillier than most that I read about on these forums.
It's just something the internet does to people. Someone says something wrong and you feel compelled to correct them. What if someone believed them? Then they treat what you said the same way and pretty soon you're having a futile argument in what should be a delightful preview thread.
You have already accomplished the most difficult half of solving the problem - becoming aware of it.
Please allow me to provide you with some unsolicited advice: just let it go.
While some arguments can be fun, this one clearly has gone sour for everybody involved.
The trick I use is: as soon as I feel the urge to repeat a point I already made, just don't do it. It's time for reflection instead.
The reward (not being in a silly argument yourself) vastly outweighs the cost (someone you barely know might continue to think you're wrong).
And sometimes the reflection leads to the insight that I was wrong myself and excuses can solve the problem altogether.