A "whistleblower" should reveal some secret facts. Here we have a collectiol of opinions, even if by an FSB worker.
Whistleblower in times of war is less likely. Going public with secret info is exponentially risky because of information overload and lethal punishment. Exile, sedition or refuge-seeking would be more rewarding to a top-notch professional wanting to spill the beans to the West.
If you say "we're stressed, things are not great, the Chechens are unstable" thats... not a direct leak; nothing super actionable there. Maybe enough to be hanged in Putin's wartime Russia, but nothing that will stop an offensive.