As a person with trauma, who has had trauma all his life, I find social interactions draining and stressful. I have trouble developing trust, which makes it difficult to bond with others. And which makes me more lonely in a crowded room than I feel right now sharing my thoughts with you all on the internet.
I guess I'm curious how this study would fair if it was done on self-described introverts. I value my friends, but maintaining and developing those relationships is a burden rather than a joy for me.