It's interesting that you mention Tik Tok, since it's by far the newest of the group you mention. Users seem to go to the next big thing, and in the case of Tik Tok, it's taken over for something else before it, just as Facebook did. Twitter and Instagram have yet to have serious contenders.
It seems to be that once those competitors show up and prove to be stable and interactive enough, people start making the shift. As big as those four are, it will take some doing, but maybe a crypto based social media app is what people will finally gravitate to.
RE: Wanted: HIVE Content Consumers