Why wouldn't taking anyone intelligent and capable result in more diversity? Are you claiming white males are somehow inherently more capable and intelligent?
The problem is that outside the likes of Srinivasa Ramanujan people need a hell lot of education to become the best. And unlike innate talent education is not equally distributed in society.
So the pool is very skewed.
So, lower the barrier to getting started and learning from hands on experience. Github and other sites host code, discussions, and documentation for more projects than a lifetime of hacking could touch. No one knows who you are behind a handle.
You seem like one of those people who thinks that quotas will magically improve companies, diversity, and people's lives. You are falling victim to the soft bigotry of reduced expectations. This isn't fair, particularly to the groups in question.