MDMA releases the chemical oxytocin, which our bodies naturally produce. The chemical causes animals to fiercely love their own, but also protect them from others — which can mean a disdain for outsiders may actually increase.

I would have to see more data or examples to take this last clause as real. It sounds like some off-the-cuff dualist BS conjecturing. I can’t imagine oxytocin increasing disdain of outsiders just because it induces the opposite feelings toward your in-group.