you’re taking it as a given that bytedance will sell the app if this law passes. there is a chance that they won’t want to sell and then the app will be banned. (but i think this unlikely.)
also, if i’m understanding things correctly, there’s the possibility that they do sell and the app still gets banned. the article says
An app would be allowed to stay in the US market after a divestiture if the president determines that the sale "would result in the relevant covered company no longer being controlled by a foreign adversary."
depending on who the next president is, there’s no guarantee that they’ll say any sale will result in the company not being controlled by a foreign adversary. (although this past is just speculation.)
anyways. this bill will certainly raise the chances that the app will be banned in the US. (and it opens the door for other apps to get banned if the US doesn’t like the country they were developed in.)