I have met many, many people who are too traumatized to engage in "normal" sex, who have found sexual expression and healing in BDSM. Lots of people practice kink without having anything close to what someone else considers sex -- but it might still be sex to us.

The guy you're talking to is over the line. People are telling him about their lived experiences that contradict his ignorant expectations, and he's just tuning it out and continuing with his thing. He has some kind of damage that's playing out here and it's shitty that he's getting it all over us.