I believe the underlying narrative of TikTok was with government control the algorithms would be purposefully tuned to promote disorder elsewhere which is a level of control the U.S. government does not have over U.S. companies and they were jealous (although with the level of information control during Desert Storm I am not 100% certain on that). However, I think this law was very premature and should have required evidence of tuning or actual war. While soldiers may have apps they should not the spies should know better.
The China side where they have banned encryption apps also seems to be war preparation. A digital iron curtain while depressing for the population behind it is not something that can be torn down from the outside. A per app legal war seems an unfeasible use of congressional time when many Chinese smart device control apps require location to function and are on many phones. This also appears to be an opening shot by congress for putting up a U.S. national firewall if TikTok just leaves all US offices and continues business through web based offerings.