There are lots of vices and tasks that adults can usually handle but minors may not. Alcohol, tobacco, drugs (in as far as these are legal in a given jurisdiction), voting, operating heavy machinery, driving cars…

In Japan sexually explicit comics are strictly 18+, clearly marked as such, and are sold as you would sell liquor or cigarettes. Making sure children don't have access to these is a matter of public awareness and parental guidance — it seems to work pretty well there.

> I know people who have been messed up when they were very young and found it.

Messed up from lolicon (i.e., Japanese comics featuring minors in sexually evocative situations) or messed from access to porn in general (or even actual child pornography)?

As I said explicitly, messed up from freely available lolicon comics and content on the internet. The vices you list all require physical exchanges with others or would usually be noticed by adults nearby, and so they aren't really comparable.

True, unmonitored access to the internet can expose minors to things that can have an adverse effect on their psyche. But let's limit ourselves to freely available online content. Singling out lolicon (or any other form of drawn porn) seems dangerously inconsistent to me.

Violence, hate speech, gore, (adult) porn; even written fantasies containing content that may stimulate forms of destructive behaviour — the list is endless! Either you shield children from all of it (which is sensible for young children, but not tenable for teenagers) or you educate, guide, train, and accompany your child as they learn to handle an ever increasing amount of freedom. Parenting and education are key here, not banning everything that may harm a child's mind.

One might argue that the reason people get messed up if they are exposed to certain types of content at a young age is not because of the nature of the content itself, but because of other people's response (or lack thereof) to it.

When everyone else is either judging you or trying too hard to pretend that nothing happened, you internalize a sort of guilt or shame that can haunt you for life. People who have seen terrible shit in their childhood but turned out okay, on the other hand, often report that they had someone to help them understand what was happening without rushing to a judgment.

I don't know who would judge a child for seeing lolicon, since no one would know about it but the child. I would agree interpersonal emotional support and therapy needs to be a more available and acceptable resource for everyone.

> I don't know who would judge a child for seeing lolicon, since no one would know about it but the child.

Children usually want to tell everyone about what they saw. If they keep it to themselves, it's often because they understand that someone else would judge them, punish them, get angry at them, feel disappointed at them, etc. for seeing it. Their friends might have told them that it's taboo. Their parents might have acted really awkwardly around similar content in the past. Or a predator might have said that what happened in the shed is a cute little secret between them.

Whatever reasons they have for trying to hide it, it's a symptom of a society that discourages talking frankly and objectively about certain kinds of things.

Is there some study you could link to? I would think that IF there is any harm (and I doubt this since porn is very historically normal and even in classical art) it would be not significantly worse than the generic case for any such porn.

That could be likely to happen if the lolicon art were remotely realistic. I talk to artists a lot and see a lot of different art float by in their media feeds, and the lolicon stuff is almost always extremely stylized ot the point that they're entirely fantasy creatures with only a passing resemblance to humans. At the same time there's still a visceral shock to seeing the occasional rare picture where the characters actually look like human children.