Comment by accrual
TikTok is used for far more than cat videos which is why it's a considered a threat to those in power. There are freely flowing ideas and narratives which they cannot control - except now they are by restricting access to it.
Instagram doesn't have the same culture at all and it's not a substitute. TikTok is a like a digital "third space" for communities, and just like the real life equivilents, is slowly disappearing. People without community are easier to control.
Why shouldn’t TikTok just divest, then? Bytedance could make a huge amount of money by selling TikTok. And then that huge influx of money could keep TikTok operating forever. The fact that they’d rather shut down is pretty telling.