Not sure why you were downvoted. Our infrastructure worldwide relies a lot on location data, incl. GPS data.

There is actually an article from the New Yorker answering your question: much less traffic, all planes grounded, no train, etc. [1]

> The U.S. Department of Homeland Security classifies sixteen infrastructure sectors—including dams, agriculture, health care, emergency services, and information technology—as critical, and therefore particularly vulnerable to sabotage. All but three require G.P.S. for essential functions.

[1] https://www.newyorker.com/tech/annals-of-technology/what-wou...