The act of organizing a conference makes one a leader for their technical community. We all know we have a diversity problem. And conference organizers are responsible for helping address that problem. Leaders should lead.
Are you going to blame the technical community because 13 year old girls don't like it?
I think that's a false dichotomy. By doing nothing, we help foster the problem.
Personally I think quotas is one good way of helping solve the problem. The idea being that they counter the existing bias against some groups.
If there is no existing bias, quotas are indeed "unfair". If there are existing bias, quotas will be unfair to individuals. I still think quotas can do good overall.
If there is bias, and you cannot see it: you will perceive quotas to be unfair.
This was a few Rubyists trying to do something for their community - not interviewing for McKinsey.