Most apps have child abuse problems. Of all the examples of how modern corporations externalize risk and internalize profits, I think the child abuse for ad revenue on content is particularly egregious (one example link here is that the children are the viewers and consumers of the ads (advertising to children being worth more money in many contexts), and the child abusers post massive amounts of content that children will consume (and hence watch the ads on), which the abusers then leverage into contact (and from there abuse); there are plenty of examples).

Google researched this, it would take 30,000 employees to manage their communities against child abuse effectively (not watch all content; a mistake people always seem to make when I say this). This would be about a fourth of youtube's suspected profits, so of course that isn't happening. Instead relying on machine learning and other clever solutions which are either ineffective or make the problem worse (youtube heroes for example).

Tumblr had similar problems and got temporarily banned from app stores over it. They of course banned all NSFW content, which didn't actually fix the problem (notably the beacon posts, and their crappy design (click share on child pornography to report it), and the ease of access to children; problems that Kik shares as it happens). And lets not even get started on the easily accessible chat rooms and online games targeted at children (quick, how hard is it to make a chat app, download some shitty cartoon graphics, and access a webcam? what like a day of effort? yeaaa... search "kid" and "chat" see what comes up, go on, I'll wait).

I would say that this would be a way to disrupt the chat market, but I don't even think anyone cares (worse than that, it will probably come off as idiotic, "kids are early adopters" anyone?). People will care when it comes to invading privacy: "think of the children" will be used to introduce stricter controls like it always has. But children are being harmed by companies that actively invade our privacy already (and hence cooperate with the powers that be), they get a free pass because it was never really about the children. Of course the irony is that this app wasn't shut down because of child abuse problems, but because of financial/regulation problems and a pivot. Running a cryptocurrency actually probably does have less criminal risk (and for that matter moral hazard) than running a chat platform (which is an insane statement, but that's where we are).

The only sorta-workable solution I have (that isn't stricter regulation of tech companies and chat platforms) for this issue is federation. Creating local chat platforms backed by local moderators (who have a stake in a positive platform) tied to real people (removing anonymity at the local level, but keeping pseudo-anonymity on the broader internet, but then you also know your system admin), this should overall encourage better behavior. But also children can be restricted to the local community (where it is safe, and they also can't make a nuisance of themselves), the federation would bring them content they could comment on and discuss with their friends (e.g. they could watch and comment on their favorite youtuber's videos, but conversations would be kept local). And of course a parent could white list remote friends, and communities can have "penpal" or "sister" communities that they whitelist in their entirety because they have close ties. Mastodon and other open federated social media platforms are working towards things like this.

This of course comes back to the parental control issue (most notably that parents suck at using them). But the point I would make is that such systems would be community backed, and offer better parental controls. Mixing in things like community ran game servers, document clouds, and so on would also do wonders.