I'm an extremely liberal-libertarian free speech and free information advocate. I grew up in a world where as a 12 year old, on IRC, in 1992, I had people sending me fetish porn and child porn, and I developed the belief at that age that that was fine, if you were 12, you had the right to see anything you could, including other 12 year olds naked. But this was not something most 12 year olds were exposed to, and by the time I was 14 I was pretty clear on why they shouldn't be.
We live in a world where there is no such thing as a "ban". Oh, I know, I hated bans and railed against bans, and I don't think the government has any right to ban anything. But a ban is just an obstacle to people who want to violate the norm. A ban is only a way for societies to set up barriers between people and bad shit which is bad for society, and sometimes it's okay for there to be barriers. In 1992, the reason most kids were basically incredibly innocent and had never seen any porn at all at 12 years old, was that the barriers to it were reasonably high. If you were some kind of command line warrior child who could figure out IRC over dialup, then yeah, people would literally mail you brown paper boxes with porn tapes on VHS.
There are, actually, boundaries on what is too traumatic to show someone. Personally, I'd like to obliterate the behavior that fuels those things, rather than need to address the downstream issues of people seeing them. But there are things that are poisonous to society because they poison individuals, and there's a role for society and government to play in prohibiting those things, or at least preventing their spread as much as possible.
There is evil in the world, and it is sometimes necessary to stop it. Free information is not an unalloyed good.