This is basically irrelevant as long as there are only a small number of gigantic providers. If the shareholders disagree with the government, the company will do what the government wants.
This all played out with crystal clarity over two decades ago, when the CEO of Qwest (then one of the five largest carriers) refused to spy for the NSA. So they threw the CEO in prison and drove the company to the edge of bankruptcy (it no longer exists).
That was the last time a "privately owned" telecom giant ever said "no" to the NSA.
https://www.vice.com/en/article/pgg7q7/the-telecom-exec-who-...
https://www.eff.org/deeplinks/2007/10/qwest-ceo-nsa-punished...
https://www.businessinsider.com/the-story-of-joseph-nacchio-...
https://www.washingtonpost.com/news/the-switch/wp/2013/09/30...