Well, of course they aren't comparable.
But almondcakes said "It is only feminists that are called upon to use a higher standard of accuracy when talking about men. It isn't a general language rule at all" and I don't think that's right -- I think it is a general language rule when you are saying something potentially negative. That's all. It doesn't mean that I am equating any of the groups or any of the negative consequences.
I think that there is a general rule in English (British English, anyway) that if you make any statement of the form "[group of people] are or do [something negative]" people will object and say "that doesn't apply to all members of that group". That doesn't mean that all groups that you could slot into that statement template are comparable. It doesn't mean that all negative qualities or behaviours that you could slot into that statement template are comparable.
It could be toddlers having daily tantrums or teenagers being self-centred or old people tutting on buses or truck drivers being hairy handed or men raping or politicians being corrupt or members of the Nazi party being complicit in genocide (even then someone will be along to reference Oskar Schindler and discuss the socioeconomic implications of not joining the Nazi party at the time).
This doesn't mean (I hoped that would have been obvious) that I think teenagers being self-centred is comparable to men raping women or to the Nazi holocaust -- it's just an observation that WHATEVER the context of your sweeping "[group] does [bad thing]" statement, from the trivial through to the incredibly serious, someone WILL come along and pick you up on it. So it's not just feminists who run into this. That's all.
I do think that the validity of the objections to the generalisations, and how much we'd classify them into "nitpicking and derailing" versus "probably a valid point" will vary according to what the group is and what the negative thing is. But I'm not really trying to get into that, just arguing with the (IMO untrue) assertion that it's ONLY feminist discourse where the "not all [whatever]" happens. If it weren't for "how very dare you generalise about [group]?" posts on every subject under the sun Mumsnet would have about half the traffic it currently has, to begin with...