"You're totally right about X and Y. I think the only thing we disagree about is Z". People like being told they're right, and you then downplay the importance of the actual remaining disagreement. Often that lowers the stakes for people. They've already "won" since you agreed with most of what they said, so the rest becomes less important.

Repeating back what someone said (specifically: trying to mirror their exact words as best you can remember them) also has proven psychological effects: increased empathy and calming of your own emotional response and theirs.

It's a component of a few psych frameworks around improving interpersonal conflict. Ref: https://hartsteinpsychological.com/the-power-of-active-liste...

Short template form is "What I think I heard you say is (repeat their words as exactly as possible)? Did I get that right?"