I'm a man in my 40's, my experience is similar to yours - I have had the misfortune to meet a couple of nasty blokes, but the vast majority are decent, hard working, good husbands/boyfriends to their wives/partners, good dads, upstanding members of the community.
I've never met any men who hate women, but I have encountered a few women who, like many on this thread have a deep seated mistrust / disliking for men.
The conclusion I have come to, is that in most cases, these people have had one, or maybe more than one bad experience with a bad guy, which of course has coloured their view.
There is a woman a few doors down who has had a succession of unpleasant, abusive partners, police called etc. but every time she enthusiastically introduces the new bloke, you get that sinking feeling - she is obviously attracted to an underclass of man who ends up being a wrong un, the old "bad boys" trope.
Most of us are just a bit dull and boring, but quite harmless!