You can disagree without turning somebody into an enemy.

Disagreement gets escalated into opposition very quickly, usually by tone and framing rather than by content. Once someone is an opponent, the disagreement stops being about the question and becomes about the two of you, and it becomes almost impossible to change position without loss.

Keep the disagreement about the thing. Say plainly that you see it differently and that you may be wrong. Acknowledge the part of their view that holds. Those small moves keep the person out of the category of enemy, which is what keeps the conversation useful.