Sometimes the goal of debate is just to deepen our connection with the other person not necessarily change their mind. I think the arguing happens when neither person in the discussion is willing to let the other person in. I had a FwB who I probably spent more time talking too than sleeping with and it was almost always about something political or something we disagreed on. We have a great connection and respect for each other despite disagreeing on a number of things. I've also dated guys who I could never have that deep of a conversation with and it's not because we didn't both have good arguments, it was their refusal to let the conversation go anywhere. Like when you debate with somebody on the internet and they sound so impersonal, like a robot spitting out lines that give you deja vu of other internet debates you've had before.
Half the time our opinions on social issues are just lies we tell ourselves to cover up our real feelings. Believing immigrants are the reason your life didn't turn out as you were told it would is just as much of an emotional crutch as alcohol or binge eating. In order to change that opinion we need to connect with somebody on a deeper level outside of the debate, the debate itself is kind of useless. Every good opinion changing debate connects with something in the other person.