The thing is, breathability is such a key variable, and different humans have different "tolerance" to it.
I have trekked in the rain with my Goretex jacket, and after half an hour, I'm still wet on my body, not because the jacket didn't work, but because I've perspired so much that I'm wet with my perspiration.
Similarly for the boots/shoes. I have worn those PCK (Phua Chu Kang) rubber boots, and after an hour walking in them, I come back with sticky clammy feet. No, they're 100% waterproof. And 100% unbreathable. So I still get wet feet
Of course, for most situations, this clammy wet is still better than the totally wet kind, so usually no problem. But in extreme winter situations, this clammy wet feeling is all you need to make your feet freeze... ;P
But needless to say, some people have no problems with their sweat glands, and so Goretex, or eVent, or whatever-favourite-membrane works. And there's a whole range of people in-between....
My 2cents