I wonder if we can sort of trick ourselves into more reasoned discussions. For example: before a debate have the participants (maybe the audience too) say something to the effect of "I am willing to change my position on this topic."
A very effective way I found was to identify their role models and find one that shares my opinion. For example, I have a friend who salivates to Elon Musk and I've had great success getting him to consider alternate viewpoints by casually mentioning that my opinion aligns with his.
Another more subtle way is to read a bunch of stuff that supports your point of view using their phone or PC. Most big sites these days will show you what they think aligns with your beliefs. You can use the creepy targeting they're already doing to skew the point of view your friend sees.