Great post from Jonathan Eisen.
Why is this important? Well, speaking at a meeting is important for people's careers. It helps in merit and promotion and tenure cases. It helps get their work recognized and known. Speaking at a meeting is also good practice for speaking at other meetings. Having diverse speakers also is important in terms of providing role models to attendees. And having diverse speakers helps a meeting not just be about the same old, white, men talking about their ideas. Or, in other words, it makes a meeting more, well, diverse. And almost certainly more interesting. And so on.