Because by admitting to it, they can pretend to be “transparent” and can say “those evil bad guy countries never admit to anything like this.” It’s like how redditors started joking about how a CIA agent watches their every move and then just…didn’t do anything about it. An intense violation of their personal freedom that they claim to love, and they were joking about how it’s totally fine to have a government agent watch their every move. It normalises this sort of police state where every thought and opinion is carefully controlled. That’s why they admit to it, because they know that despite all the American’s bluster about “freedom” they will always fold and accept whatever “big government” is doing.