Voted kinda important. Usually, it doesn't matter, but it helps in these areas:

1. Character creator options, especially with hair and skin tones.
2. Character writing (human world). Unless you're really experienced, it'll be tough writing well developed characters of the opposite gender. Not many games are all that story focused, so it doesn't typically matter. Same with modern settings - It would be nice to have someone from the story setting, or the staff has contacts with someone who is.
3. Having people from all walks of life may make the game more well rounded. In America, racial identity is a pretty important part of this, but I'm certain it's quite different in other countries. Even non-gamers providing valuable input would be helpful, since many of us may take for granted systems that may turn others off.
Higher spanersity has a greater chance of allowing different voices be heard. Some people may have some great ideas that can enhance the game.