People don't change their minds with debates for the same reason Jordan Peterson doesn't change my mind. I'm not some immaculate debate bro, I'm not under the illusion that winning a debate requires one side to be correct, it simply means that the other person's smarter or better researched on something than myself. Unless you've actually gone and read up on flat earthers, odds are if one starts debating you they'll pull this or that nonsense out of their ass that sounds convincing and that you don't have a response for; but you know better than to assume that just because you can't pin down why they're wrong that nobody can, and that if you were foolish enough to just agree with them because you didn't have a rebuttal on hand you'd suddenly be liable the moment someone with more sense than you poked holes in your new position. You probably aren't even going to go look up why they're wrong, you just implicitly trust they are wrong and have no reason to question that. You're not gonna waste a week researching a bunch of bullshit for that guy.

So now some communist, the bad guys in the cold war, is trying to facts and logic you about how communism is better actually and those freedom hating terrorists in the MIddle East are actually the good guys. I'm sure they sound very smart and up their own ass, but you can dismiss them just as easily as the flat earthers because you're not dismissing either of those people based on some college education you could never afford. The world that has provided the life you've lived so far says this thing, so the world is probably right and those other people are wrong.

This is why Huey Newton got assassinated. If you literally feed people's kids, suddenly you are the one providing people a better life, you are the one that actually has their best interests at heart. This is why "struggle sessions" mostly don't work. Changing anyone's mind requires a level of mutual trust that most people don't have with others due to capitalist atomization, just as you trust your friend when they say you're being a dick much more than you trust a stranger making the exact same points. This is why we go on and on about mutual aid all the time, it is literally the prerequisite to making any sort of changes. The moment someone is actually relying on you to live a better life is the moment they actually give a shit what you think.