My understanding is that they can prevent you from removing warrant canaries but they can't force you to continue announcing "I have not received a secret warrant".
In places where there are limits to what the government can do to an with you, its possible to resist.
EX: https://en.m.wikipedia.org/wiki/West_Virginia_State_Board_of...
The US government can’t legally compel you to lie, but may restrict what you can say.
We know that the legal bar for forcing someone to speak or not speak is high (compelling state interest), but national security has usually been held to pass such a bar.
Warrant canaries are nice to have, but viewing them as something which provides proof of absence of government meddling is incorrect.
That wouldn’t even be illegal, since they never hit you with a wrench - you just imagined they were about to go xkcd on you
[1] https://en.wikipedia.org/wiki/Warrant_canary