For my Ford, the manual was very helpful. Taking a look at the fuse box diagram, I was able to remove the fuse for the modem.

Thankfully I was able to verify that the modem power was secured because when I enter the infotainment settings to view the modem serial number, I can no longer see the modem serial number. It is just blank.

This won’t work for all vehicles because the modem may have the same fuse as critical equipment.

There is no evidence that it is banned. ByteDance just made the same app for the PRC market

https://www.snopes.com/fact-check/is-tiktok-banned-in-china/

Well the CCP does exert considerable control over TikToks parent company ByteDance. The CCP has already utilized data from TikTok to track protestors and other “dissidents”

https://apnews.com/article/tiktok-china-bytedance-user-data-d257d98125f69ac80f983e6067a84911

No the CCP does not own Tik Tok but it might as well own it.

Unfortunately this situation is not unlike what the US government likely does. However, hopefully this precedence building policy recognizes that data privacy from 3rd party entities is needed. Will that standard be applied to US companies? Not likely any time soon but I’m optimistic.