As someone who would be proud to be “accused” of being a SJW, I agree that many displays of emotional support on Tumblr are just that: performative displays. Yes, young people are unpracticed in establishing boundaries, but I think the harassment described by the OP can be explained by old-fashioned entitlement; people who think others exist only to satisfy their personal fantasies and won’t respect any boundaries, regardless of who is obliged to establish them.