When you're white, and you're male, technology (as a career field) is pretty accessible. And here's why. You can open up a newspaper or a tech blog or whatever, and many of the major important people in the photos staring back at you basically look like you. And that's nice, because you can be reassured that someone with your background and origins has a place in technology.
If you're not male, or not white, you have to look a bit harder. Sometimes a lot harder, indeed, to find people who both look like you and are doing what you want to be doing professionally.
Now, you'll give me an argument that looks just shouldn't matter. That we should look at people's minds and ideas, not their skin color, in evaluating their contributions.
And while I'm sure such an ideal feels reassuring – it's bunk in this context.
Diversity of "race" is really a proxy for diversity of background, experience and origins. For maximizing the varieties of life story represented.
It's useful to do this because diversity of experience leads to diversity of solutions. Diversity also breeds further diversity, as people with wildly different backgrounds feel more welcome into the fold.
So when we see people helping to lead a community, and some of those people aren't like the majority, that's encouraging. It says that even though a given person is "different" from the norm, they are welcome, they may be successful.
Star Trek is lauded for this reason. Actor Nichelle Nichols was thinking of leaving the show. None other than Dr. Martin Luther King implored her to remain – he believed a black professional woman on television would be a crucial role model for young people. (In her childhood, Whoopi Goldberg is said to have screamed, "Hey Mom! Look! There's a black woman on the TV and she ain't no maid!")
And you may argue, well, why should diversity matter? Let some people do some stuff and other people do others. And I'll tell you that position, on top of being lazy, opens us up to many missed opportunities. In technology, we want as many different sorts of humans as possible all working on our hard problems. If STEM is a country club for white guys, that leaves out a huge chunk of the population who might otherwise make great contributions.
One last thing. When you say stuff like "Wull, shucks, what were they supposed to do? Find a token [non-white-male] to fill the spot?" you make it sound like you don't believe there are any people but white guys with useful things to say on the subject of the conference. Careful with that.