As someone from the third world this leaves a very bad feeling if it happens. I do expect it runs into legal hurdles before that.
Neither Apple nor Google have found TikTok problematic enough to delist them from their app stores. Neither is there charges that TikTok may have broken US laws.
Banning something which hasn't broken US laws, on arbitrary grounds shouldn't be possible.
The President shouldn't have authority to ban anything at all let alone an app available through privately operated app stores.
Also dictating which apps an individual can install/not install shouldn't be the job of the Federal Government.
All indication is that the president does not have authority to execute an outright ban of the thing.
Also what alarms me the veil of secrecy on the procedings. The proceeding of the CFIUS should be made public in this regard.
At this point US is seemingly acting like a dictatorship with very less transparency.
Policies and decisions should be debated and argued before they are executed, not merely justified after the fact. That's what US and a few oher democracies have turned to doing in recent years.
Ultimately I feel that it is US who has been more to blame (contrary to much of Western media coverage) for the deteriorating US-China relationship, and drumming up the chorus for a new coldwar. Chinese policy seems to have not significantly changed in the last 5 years towards the US, but on the other hand US seemed ever more keen and eger to pursue a hostile attitude towards China.
With the pandemic and with genral economic malice affecting much of the world, I don't think a path of increasing hostility and conflict is what the world needs.