Hey. I will be frank and say that my first instinct to this was to interpret this as trollish, since it is so foreign to my experience, but I respect you and your work a lot technically and so I will take what you say seriously.
I can only speak from my experience in Boston and in the Bay Area, but "the intolerance thing" is definitely a problem here. Maybe it isn't in Europe -- I haven't been there, so I don't know. (I'd love to live there some time!)
But the problem we have is that there are, in fact, people who honestly believe that other types of developers -- whether women, or driver developers, or web programmers, or whatever it is -- are lesser people who are not worthy of that sort of respect. And so when people make these sorts of jokes, on the assumption that everyone around them knows it's a joke, it only convinces the people who actually behave that way that other people share their beliefs.
And if you have people -- driver developers, women, etc. -- who have been told, in seriousness, "oh, you're a driver developer, that means you're not good enough for real programming," or "women aren't as smart as men, scientifically", or whatever it is, any jokes along those lines also serve to convince _them_ that this is normal and this is what the community truly believes.
I agree that in an ideal world, the Debian diversity statement isn't needed, and we ought to be able to make these sorts of jokes. But we live (at least I live) in a non-ideal world, and there is value in saying, clearly and with no chance of confusion based on context, that we do value diversity and that we don't actually think that driver authors are lesser people.