Despite the scant / non-existent evidence for porn being such a bogeyman, it keeps getting cast as a scapegoat which is quite frustrating, so I am going to have to go over this... Again.
Even if online porn "might" be "problematic" to someone out there, it would not be anywhere remotely near proportionate to engage in censorship (or privacy intrusive measures, which among other things might pose a security risk), especially as it can be free expression to someone, and expression which someone might casually share as part of their more general interaction / engagement with others.
Sometimes, restrictions can lead to services becoming inaccessible entirely, rather than simply limiting them to people over a particular age.
A typical recommendation is sex education (perhaps, teach someone about respecting others boundaries?), not censorship (which is harmful in it's own ways). I don't mean criticizing someone for telling an offensive joke.
The science isn't really showing porn is this awful thing:
https://www.tandfonline.com/doi/abs/10.1080/00224499.2015.1023427
https://psyarxiv.com/ehqgv/
Two studies showing porn is not associated with sexism. One carried out by German scientists, another carried out by Canadians.
https://qoto.org/@olives/110462274531891870
American scientists carried out a meta analysis of 59 studies. They found porn isn't associated with crime. A meta analysis is a study where someone studies studies.
https://pubmed.ncbi.nlm.nih.gov/31432547/
Nor does it necessarily seem this is the case among adolescents (the meta analysis also points to that). Here, the minors who used more porn engaged in less sexual aggression.
https://www.psychologytoday.com/us/blog/all-about-sex/201601/evidence-mounts-more-porn-less-sexual-assault
https://qoto.org/@olives/110400288665794817
There are even studies (across the United States, Japan, Finland, and more) showing that porn is associated with less crime, even among criminals.
https://pubmed.ncbi.nlm.nih.gov/31042055/
While an older Dutch study showed there might be worse levels of "sexual satisfaction" among adolescents using porn, a Croatian lab failed to replicate that.
https://www.sciencedirect.com/science/article/abs/pii/S0747563222001637
This is a meta analysis on sexualization in video games. It finds that studies tend to pick cut-offs where it's difficult to distinguish signal from noise. This increases the number of false positives.
There are also results which contradict the theory of sexualization being harmful. In the end, it fails to find a link between this and sexism, and this and mental well-being.
I'm also usually sceptical of apparent links, as the "scientific pile on effect" (as one described it) drives people to go looking for "links" between porn and "something bad" however tenuous it might be, or methodologically flawed an approach it might be (and later, that something is debunked, or the "link" is a phantom due to methodological limitations).
I could add it doesn't matter if they're "child-like" or "fictional children", (this is far, far more likely to hit someone good than someone bad who don't need it, and a bad actor could still do bad things)*. This necessarily excludes involvement of abuse or invasions of privacy. If it were actual real children, I'd oppose that on ethical grounds (though, I still wouldn't want to burn down the Internet / sites, because of unwanted bad actors). This is covered above but it is also kind of common internet sense.
While I'm not making a point about anything in particular, to inoculate you against potential problematic arguments, it's worth mentioning the basic precept that correlation does not imply causation.
Let's use ice cream as an example. Everyone loves ice cream, right? Well, I like ice cream. This also happens to be used as a classic example by others for this sort of thing.
Anyway, ice cream is correlated with crime. No one would say ice cream causes people to go out and commit crimes though. Just because there is a "correlation" doesn't mean it is meaningful. And that's not the only way in which correlation might not imply causation. For instance, warm weather is a far more compelling explanation for this phenomena. That might come in useful somewhere...
Here's a couple which were added for #auspol:
https://reason.com/2015/07/23/despite-all-the-panic-millennial-teens-h/ U.S. data shows teens are having less sex with each other (in a world with more porn).
Misapprehensions about porn can be more about expressions of sexual orientations than porn. In fact, we've seen an Australian news outlet specifically singling out "anal sex" as a negative thing not that long ago, who would that disproportionately impact? https://pubmed.ncbi.nlm.nih.gov/29702013/ Also, moralizing can be harmful (and ineffective).
Typically, a certain amount of responsibility is put on individuals to behave in a manner that is reasonable to them, instead of looking for a scapegoat whenever someone behaves in a manner which could be argued to be negative. This isn't to discount external factors (i.e. socioeconomic ones) entirely but there isn't always something sensible which can be done. People live their own lives.
Quite a few things which might get blamed on "the porn" are actually general mental health issues which could be dealt with more normally, and crucially, without conflating it with porn (which might even detract from dealing with someone's actual issues).
In fact, online censorship has increased in quite a few ways over the past few years and it doesn't appear to be any sort of panacea. It has, however, created a number of harms in it's own right, including even murder by practically forcing some sex workers to work with more dangerous clients. It also provides a space for abusive bigots to dwell in.
An addendum (from another post which might be useful to add useful context, we won't delve too deeply into this section):
An additional bit on why "porn censorship" (perhaps, even some themes) is bad.
Some points about censoring fictional content there (censorship is a bad idea):
It might fuel someone's persecution complex, especially in the context of *. The idea of a dangerous world where people are out to get them. Feeds anxiety, alienation. It's happened a fair bit. It doesn't seem to do anything positive.
Someone might be more inclined to see someone as an idiot or crazy (that's not wrong, lol). In any case, it poisons the well as someone is not seen to be credible or competent in these matters at all. Promoting distrust doesn't seem like a positive outcome.
It violates someone's free expression. People have these things called rights, that's important. This point comes from the original post, I'm aware I've covered this here more generally, still there may be value in reaffirming it.
Bad people don't need it. They could still do bad things. Good people are who'd suffer.
It violates the Constitution. Multiple constitutions.
Punishing someone because they resemble someone unpleasant isn't good. Also, due process still applies, in any case...
Can be a coping mechanism.
