What does it matter what he created before?

Stephen King created Christine and drives cars, but it doesnt mean all his books are about cars!

I think you will find that even as exec prod, the stars and the BBC have more than just a little bit of input into the show!

To just say "Oh he is gay, created a gay show and is trying to infiltrate everything with gay!" is a bit shallow!

The fact we live in an age where gay people are a lot more prominant, would suggest that its gonna reflect in tv shows.
And its hardly dominant in the Doctor Who episodes.