Furthermore the NSA/FBI/CIA want all their spying behavior to be secret. If you have to bend a lot of small knees then someone's going to fib before they get the data they want. And moving off a small company that's bent the knee is way easier than moving off FAANG, which can keep secrets[0] and has your balls locked in a vise.

[0] Because, among other things, the whole "Surprise and Delight" doctrine demands internal controls and secret-keeping discipline not that far off from an actual intelligence agency