Correctly moderating Facebook, blocking recalled/bogus/questionable goods on Amazon, or keeping Google's search index pruned of scams and misinformation, are fundamentally problems that requires armies of trained humans, well-thought-out and transparent process, and potentially independent or state oversight to keep it all on the rails.
It's much cheaper for them to buy racks of servers, and occasionally shrug their shoulders and blame algorithms. I'm amazed that legislatures throughout the world have been willing to accept that behaviour for so long. It's not like the problems can be explained away with "it's an insignificant business with no political or commercial influence", or "it's a 6-month-old startup firm that made beginner mistakes because they couldn't afford to do things properly".
Break them all up. Even in a world without Google and Facebook, enterprising nerds will be encoding H.265 via smoke signals to ensure we get our cat videos.