Why is it less interesting, why does skin color matter? Would be it be less interesting if all speakers wore plain white t-shirts too? Why do you care at all about anything other than the content/experience?

Your comment implies that you think that content/experience is orthogonal to a diverse speaker group.

I strongly disagree. I think a diverse speaker group leads to overwhelmingly better content and experience.

I think this extends much further than gender or race, however. I think this extends to the totality of human experience. I have a great interest in seeing the technical community encompass as wide a range of people as possible.

I want this partly for reasons of equality and fairness, and partly for purely selfish motivations (plainly that I want to work in an industry made up of people with a wider range of experiences, it makes me happier).

I think conflating a desire to see a diverse population of speakers to people's t-shirts probably means that you and I aren't going to see eye to eye on this subject. Which is fine, as I don't think you're a racist, or sexist, or a terrible person.

I do feel pretty confident betting that in 200 years, we'll see a much more heterogeneous makeup of both speakers and conference attendees, regardless of whether an active effort is made to make that so (it'll happen eventually).

Some might say if that's the case eventually, than shouldn't people just pretend that it's the case now (in which case drawing attention to gender and race is actually doing more harm than good).

I'd argue that if people agree that that's what the future is going to look like, and by most accounts, that seems like a better future, than why the hell aren't we doing more to turn the present into that future.

A diverse population doesn't necessary mean different skin colors. In this case diversity, to me, would mean people that work on different technologies, proprietary vs open-source, web/mobile/enterprise etc, small studios vs big co vs freelancers; it's a software conference. I don't give a damn what a speaker looks like, and also don't have any reason to assume they share anything besides being british and liking Ruby. And what about women, why did nobody complain?

I do support pro-activity measures in education/work, but I don't think being conscious (or "pro-active") about inequality all the time does much good for equality either.

A diverse population absolutely means different skin colors. And different genders; and different income brackets; and different religions (including lack thereof).

The world is an incredibly diverse place. Full of people, all with different experiences. I argue that the more all of those people get exposure to one another, the more we can all learn from one another.

And I don't mean in a "everyone has an interesting life story to tell" way. I mean that our experiences absolutely inform our thoughts and decisions. This is as true for thoughts on technology as it is for any others.

Everything that you (and by you, I mean all of us) have to say, everything that has shaped your outlook on the world (including but not limited to technology) is inexorably linked to the sum total of things which have happened to you.

And if I grew up somewhere else, or am of a different gender, or have a different religion, than that's less total perspective that I have to inform my decisions.

So I don't care what specifically a speaker looks like; but I do care that huge sections of the population are way less likely to be sharing their experiences.

And if you read the tweets which seemed to cause all of this, the overwhelming majority are people complaining about a lack of women, including numerous ones listing groups and people the con organizers could reach out to if they wanted help in trying to make the speakers more diverse (advice the organizers seemingly took to suggest that they should select some woman speakers to "balance out the male-heavy selection"; which isn't what was offered).

I can appreciate that you don't think every situation should be an excuse to rail against inequality, but I think it's important to be conscious of these things.

Well, we don't seem to be talking about the same thing; I was talking of a diverse population in the context of a technology conference. Despite personal contact being a huge part of it, the focus for presentations is on technology, not people. Selecting for cultural diversity is not a goal - it could be, but it shouldn't be a crime if it isn't.