A New York Times reporter said employees had trouble getting in, and I don't see a retraction. So I believe that is true:

https://twitter.com/sheeraf/status/1445099150316503057

I briefly worked on access control a long time ago - aren’t they supposed to cache credentials locally so that individual doors still function autonomously during a fire / loss of power and comms?

I think you mean repeated uncritically by NYT. It doesn't even make sense, as reported. Yes, maybe to get into the cage in a shared DC, but not individual servers, and it turns out neither was necessary. That's a rehash of an old Google story.

Another bit of misreporting (e.g. The Verge) is that this was "one of its main US data centers in California" when there's no such thing. The seriously big heaps of hardware are elsewhere and they're not shared, so there are no cages to force entry into. I've been in one; no cages in sight. I know which facility they're talking about, and its only distinguishing characteristic is that it's close to where relevant people live.

And then retracted by NYT:

> Correction: Oct. 4, 2021. An earlier version of this article misstated a Facebook team’s means of getting access to server computers at a data center in Santa Clara, Calif. The team did not have to cut through a cage using an industrial angle grinder.

It looks like they retracted/corrected the angle grinder thing but they didn't use a retraction yet for the "access to office" info, maybe that means that was correct? (for a section of the FB workforce, of course).

Not to defend politicians looking to gain political mileage from everything, this is not a far-fetched claim. Current Indian government has blocked websites and shutdown internet access wholesale to towns and even whole states citing many reasons, and multiple times in recent past. Latest was internet shutdown in multiple Rajasthan towns apparently to prevent exam takers from cheating on a test.