When it comes to censorship and kids, the parents own the job. I understand that the social media space is a vast environment and most of the time parents are not around to see what their children are doing or watching, but it is the duty of the parents to censor whatever those children see.
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This is why children shouldn't be allowed direct access to the internet until they get to a certain age and have been properly educated on how to use the internet and most especially, what to expect from it and what to do if they come across illicit or suggestive content.
Except for those content that boldly have their audience as children, the platform is not to blame. Every platform has their target audience, if their target audience is adults or youths, then children shouldn't even be on such platforms at all.
But when it comes to children content and it still carries illicit or suggestive content, then the platform has a lot of work to do to ensure that they are serving their target audience in the most appropriate way.
As a parent there's a lot of work to be done. Taking time out to first watch or scrutinize properly what your child is going to interface with on the internet is one of them. Those platforms are looking at how to make money and even though some of their content may not be considered as appropriate for you, or your child, you cannot expect that they will truly tone it down.
But you as the parent can decide what your child interfaces with, first by educating them based on your moral standards, then checking properly to see that every platform they interface with or show interest in, has the appropriate content for them.
Just the way parents rigidly investigate the schools their children attend and the friends they keep around them, parents should also take it upon themselves to know and control the websites their kids so much as to scroll by.
This is going to prevent the kids from exploring content that are not for kids or don't associate with the moral values your family upholds.
I don't think that if a rule is passed across now concerning uploading selective content, the internet would suddenly become a safe space. And if parents just hope that the platforms would upload more selective content without going ahead to check it out for themselves, they may come to a total disaster at the end of the day. They may even lose their children to social media.
I think having the parents censor the content would be most effective than asking for platforms to tone down on their content. The content has its own audience, there are people out there who want those content, that's the first reason the social media platforms wouldn't even want to follow through with such a law.
Basically, parents should stop exposing babies to social media. I don't mean toddlers of course, I mean children who are barely old enough to think for themselves. Especially the ones who have not been told about all there is to know about the social media space. If such a child should go online for whatever reason, the parents have to be there, or a trusted guardian, to censor whatever that child is doing and guide him or her appropriately.
Now technology has evolved, there is parental control for everything including parental control software that can help parents block harmful activity, track their activity, and set time limits so they don't dwell on a platform or on social media as a whole, for too long.
If this can be achieved by most parents, especially when it is absolutely important that the child goes on social media, then the children will be largely protected from wayward content.
I am of the strong opinion that if a child has no business on social media he shouldn't even have it as an option, especially when there is no adult person to watch or censor what that child is doing. If you leave an underaged child with a device, active data connection, and freedom, that child is bound to explore unsafe and inappropriate content; it unnecessarily exposes the child to every vice out there.
So first things first, if your child doesn't have business with social media, restrict him or her until he has business with it, and when he does, ensure that it is a safe space that the child is venturing into.
Use parental controls to monitor your child's activity on the internet, do a review with that child's social media account or the child's search history to see that he or she understands the rules you must have set in place and is following them strictly, then everybody can be happy.