Excoriating - to criticize someone extremely severely
Excoriating is used to criticize someone's work or character with intense disapproval.
So, not to be used interchangeably with castigating, censuring, rebuking or reproaching, which are all used to criticize or convey disappointment.
I think it's gone out of use, if it ever was in vogue. Haven't seen it used, even though people are doing it all the time, criticizing extremely severely. They just call it a strong rebuke!