I understand you think they are saying all men, but unless you can read minds over the Internet, that’s just your opinion.
But more than that, saying “men are sexist” does NOT imply “all men”. It means “a large-enough-to-be-generalized number of men are exist”.
If you think it means literally all men (and hence feel attacked by it), in my opinion, on some level, you are sexist and are just trying to avoid discomfort/guilt by spouting #NotAllMen.
Even if someone temporarily accepts this "large-enough-to-be-generalized" definition, it may have a hard time to retain "large" part, because a number on topic is not more than 156/55000, assuming that 156 is a unique set.
"Women can't code"
Not only is it true for a substantial portion, it's true for the majority of women (and men, for that matter). But would you criticize those who object to the statement?
So in addition to proving my point about how berating the people who aren't part of the problem is very common by providing an example before the ink was hardly dry on my post, you've set yourself up for attack in the world of today. You need to be more careful.
(Edit: I suspect I'm being downvoted because some people may have a hard time understanding I'm not just being rhetorical about people saying it's all men, and that it's especially men who think they're innocent. To them, I would commend spending 15-30 minutes browsing through the various results at https://encrypted.google.com/search?hl=en&q=all%20men%20are%... . Not just a scan through the results to confirm your prejudices, but to actually look at the conversations happening, which is why I specified 15-30 minutes and not just "a glance". And while I'd observe it may not be "the new york times" for all those results, it's not just "Joe Bob's Blog & Grill" or Tumblr for those results either. I'm also not saying that every last result will say that, but the existence of results refuting the argument also point to the fact that it is being deployed.)