> Their preference to shut down instead of receiving tens of billions of dollars would be a clear violation of a company’s fiduciary duty to shareholders for any normal company

This is only true if you assume the US is the only market that matters. But TikTok is very much an international phenomenon, and selling would likely harm the company far more than a couple billion. Firstly it would give another company everything they need to run a global competitor to TikTok, including software, infrastructure and userbase. Secondly it might encourage other countries to also force TikTok to sell.

Giving in here would be the beginning of the end of TikTok and could well be argued to be a violation of the company's fiduciary duty to shareholders. It would be the ultimate version of chasing short-term gains by selling the long-term future.