That the content is promoted to create disorder. Facebook has similar issues (they're even being sued for contributing to genocide) but they were never accused of the same thing (but mostly of negligence).
This thing started with Facebook being accused of being the conduit for the stealing of the 2016 election through 100K worth of ads featuring Bernie shirtless. It's hard to remember because they got utterly bored with it eventually, and they have relatives that they brag work at Facebook.
Facebook wasn't created to create social disorder as a first principle, it was created to be addictive and make MarkZ and crew billionaires. TikTok is being used to do something similar but it is completely designed to do that by a foreign power and use algorithms specifically to damage the psyche of westerners with distracting videos, tuning them to give just enough of a dopamine buzz to keep you there and coming back, and in general distract youth from pursuing more enlightening and educational activities while building a psychological profile on them to be filed away for future clandestine purposes. Or that's just my 5 minute take on it.
