I'll say it:
All other things (education, experience, interview, etc.) being equal or close enough between two candidates, one of them being a white male and the other being someone in a racial or gender minority class, yeah, I'm going to hire the person in the racial or gender minority class.
It isn't for a metric - it's because, all other things being equal as you stipulated, a person from a class not normally found in the field is likely going to have had to overcome obstacles and challenges on the way there that the other candidate has not.
Let's look at some reasons why the minority candidate who is otherwise equal to the non-minority candidate is the better pick:
1) In every single discussion of diversity in tech on Slashdot, people will trot out REASONS why minorities don't do well in tech: Black people don't do well because they get called out by their friends and families for acting white if they go to school. Women don't because they get called out by other women for being in such a nerdy profession. Etc. etc. etc. If that is true, then yes, I want the candidate who has demonstrated persistence and determination in the face of hostility. They will be use to adversity and overcoming it, and as a hiring manager I will want that in a candidate.
2) In every single discussion of diversity in tech on Slashdot, people will trot out BIOTRUTHS about women and minorities and why they are not well represented in tech. If that's true, then yes, I absolutely want the candidate who is exceptional and defies their biology to have somehow managed to be equal to the non-minority candidate. There's more potential for them to be exceptional in other ways, and as a hiring manager, I want exceptional people.
3) If everything else is equal, why NOT hire the candidate who will also improve an arbitrary metric? As a hiring manager, I want to not have to have people crawling up my ass telling me to do things just so the team looks better, and this would reduce one more thing people could crawl up my ass about.
So yeah, unless you're a fucking idiot, hire the atypical candidate when they are literally close enough to equal that flipping a coin would be the only "fair" way to determine who to hire. Duh?