We've run a similar study and for the company we were hiring into we found blinding in that specific case had no effect on race or gender but drastically improved socio-economic diversity. The hiring company already had equitable hiring on gender & the candidate group wasn't racially diverse enough to make a conclusion.
Would I generalise that result to all organisations? No way, and neither should you.
If you can find the study you're thinking of I'd be interested to look at it.
So why do you think there is such a disparity in outcome?
Edit: Google says that their diversity platform is non-discriminatory because they're not changing their standards, but rather looking harder for qualified diversity candidates (paraphrasing). This makes the gargantuan and probably unwarranted assumption that there are a lot of these candidates not applying and that 'looking harder' will find them.