They were never trying to actually argue the founding fathers were antifa.

Then their comment was irrelevant. That's what the person I replied to said, so if they disagree with that position, they should've simply upvoted my refutation of it and moved on. But y'all are obsessed with infighting and attack anyone you suspect of being in the out-group at every opportunity.

excluding any state from the definition of antifascist.

No, I didn't. I said that slaving colonial empires are not antifascist, that does not include all states.

The followup is the pointing out that China and Russia therefore are not antifascist.

Which is utterly irrelevant to what we were actually talking about.

You tried to handwave it but then got pushed into defending the American prison system because it’s better than chattel slavery.

"Defending" is liberal's favorite word, it seems like. If you had straight up asked me, "is the American prison system better than chattel slavery" I would've said yes, without any of these games. I don't consider "better than chattel slavery" to be "defending."

A small correction that I also implied certain Marxists can also be antifa.

Just not the ones running authoritarian, heirarchy driven states.

Also you could certainly argue that the conscripts themselves are still antifa or otherwise on their individual merits, but that breaks nationalist brains.