tumblr site here. I'm not involved in the organization of the campaign in any way, but do wholeheartedly support it. If you want more of the backstory and what all is entailed, check out this blog post by Ellen Oh.
In some ways, I feel it should be self-evident why we need diversity in literature. That the more stories the better, that disadvantaged minorities can be uplifted by stories featuring people like them, that the more inclusive our society is the more we all have to gain. But there is a counter argument that always comes up, and it actually has some merit. I want to look at the other side and give it due diligence, because you can't win an argument on the internet but you can discuss topics in a civilized manner. Really - it's allowed :)
No one actually says that diversity is a bad thing (if they do, they can be safely ignored). But some people worry that the push for diversity means attacking those who are not diverse. It's a worry that we will over-correct and any story with a white male protagonist will no longer be allowed. The fear is normally voiced by white males and those who have achieved success in the current system. It's perfectly natural and understandable. And it's actually a good point.
The thing is, diversity includes white males. It includes the majority. It has to, otherwise it isn't true diversity. A world where every character is a person of color, genderfluid, or a little green alien would be just as bad as the current situation. The people who are pushing for diversity need to understand and express this clearly - everyone, including the old guard, including white men in power, including those who have succeeded in the current system, is welcome in a diverse world.
The problem with the way things stand is that the playing field wasn't level when it was created. The argument that white male writers have a disproportionate amount of success and recognition because they have achieved (earned) it ignores the fact that they had a leg up to start with. The entire world (in this country at least) is geared for them and if you continue to let the status quo exist it will reinforce itself. There does need to be some tearing down, digging up the earth to flatten the high ground and fill in the holes that exist. Then things can be judged on their merit. Then we can let the better man (or woman or little green alien or whatever) win.
That does mean that diversity will get an extra push. That those without privilege will get more spotlight time and extra opportunities. It's not a head start but a chance to catch up. It's not about weighing down those in front, but distributing the load more fairly. Once we're all even, then the race can start again.
In the mean time, rest assured that people will still buy stories with white male protagonists. Good books will still sell because they're good (and bad books will still sell because many people have bad taste:). The world will not change overnight, but it does need to change. Diversity includes everyone, so everyone should be on board.
There is an undercurrent to the argument against diversity that is a little darker. The whole discussion becomes a proxy for a simpler struggle, those in power want to keep it and those who are disadvantaged by the current system want to change it. I talked at length about it in this post on a similar theme in the science fiction/fantasy world. If the fight is about power, then it's going to get messy. If those who have it won't share, then a revolution is necessary. It's the history of the world repeated over and over, and the world of kidlit is no different.