Sounds like a good idea in theory, but when i do imagine it, it seems like it might be a dystopian nightmare of the worst parts of our nature.
I think a better idea would be a regulatory environment for tech that - squeezed monopolies and oligopolies, mandated transparency, and mandated a minimal system of human-tended justice and appeals.
Presumably, any search engine that works passably well will not show you snuff films if you type in a search for something entirely different. The only people who see snuff films will be the ones looking for them.
Child porn shouldn't be on the internet because it is illegal, and if it's not on the internet, it won't come up in search. If it does come up in search, that makes it all the easier to report to the police.
Freedom comes at a price and I believe, while I'd never support such results, the scenario that includes unwanted/illegal results is still better for the pursuit of taking power and control of freedom of speech from big corps and governments in the long run.
I think a better idea would be a regulatory environment for tech that - squeezed monopolies and oligopolies, mandated transparency, and mandated a minimal system of human-tended justice and appeals.