Saw a thread talking about this on tumblr in a fandom context but I think it can be applied to the broader Internet as a whole.

I think the reason you have more people (especially younger people) calling for things to be deleted/censored online is because they grew up in an internet that's supposed to be safe. 

The internet is where you go to get famous, to talk to ppl under your full legal name, to be vulnerable and vent out all your issues that need affirmation.

You're meant to weave the Internet into every facet of your life so of course it has to be safe. Something that makes me feel unsafe on the Internet is therefore a threat against my life.