When there is a disagreement among people about a specific belief, politely talking to people with the opposite opinion can be a useful way to double check your beliefs, but when doing so, it's important to pick the best proponents of the belief and not simply the ones that are the easiest to defeat in an argument.
I think you stated a version of what I stated in terms of the wake up call is recognizing the "other side" may feel the same negative emotions towards you as you do towards them. Recognizing this, I think, makes it possible to have the polite conversations that are so important for more clear thinking and understanding.
Just as you said, throughout history "everyone was right" even though they were wrong. That's why I hesitate to hold too strongly to "one side is mostly right and the other side is mostly wrong." Does that mean I'm ready to give time and attention to flat-earthers? Well, no, but does that remove the possibility that we are actually living in a simulation and those who think of the earth as "flat" may actually be connecting to some useful truth about the nature of reality? Certainly possible for those who can think in multiple dimensions and with nuance.
So much of what you said here is valuable. Thank you, Dan. Lots of confirmation bias going on. Trying to disprove our own beliefs is one of the few ways we actually gain knowledge as described in this simple game:
My friend Sean King has a nice list of life maxims which help him with his plausibility analysis. I think that's a great pattern to use. Find some wise, useful tools for clear thinking and stick to them, always being open to re-evaluate them and refine them over time, but ultimately settling into good thinking patterns which help us all be less wrong.