I wonder why nobody is considering the most obvious solution to all this complication around what is NSFW and what is not: Children shouldn't be on these platforms at all to begin with. They shouldn't be anywhere near social media until age 14. Definitely not free roaming everywhere on the internet.
For us adults, I honestly cannot say whether moderation instigated by a company is better than moderation instigated by the users. The devil is in the details. This place isn't moderated by a company and you'd probably think the moderation here is superior to Meta's.