> I contend that the expansion primarily reflects an ever-increasing sensitivity to harm

Or maybe once you've weaponized a concept, it's tempting to use it as much as you can.

When being a nerd stopped being shameful and started being cool, all the cool kids started calling themselves nerds for liking Avengers and Harry Potter - why wouldn't you claim the social points that are just lying around?

And when you live in a society that rewards victimhood, when calling someone a bully gives you power over them - of course people will jump at any chance to call themselves a victim.