McCabe gave some push back when he was told to shut down the Clinton Foundation investigation in a 'dramatic call' but ultimately rolled over. Pussy.
It's a possibility, anon, but I think it's more to do with him just needing to get the fuck out of DC for the sake of his sanity sometimes.
That specific line was referring to McMaster getting fired. He failed to retain his position and was punished for it is how I read that.