E.g. my ex works in HR for a bank that has a diversity board tasked with improving diversity. Problem: The bank prefers to hire from a certain set of universities that is dominated by students from private education backgrounds, which are predominantly upper middle class and above, which means they're predominantly white.
The numbers are such that with the universities in question they can not match the overall ethnic mix of the UK while recruiting staff with the degrees they want from those universities.
Yet suggesting that one hires by merit rather than by which university they're educated at is totally taboo to even suggest, though it'd almost certainly instantly improve their diversity and raise overall skill levels.
Companies where diversity is actually seen as important will quickly realize that they need to revise hiring policies. And one of the ways to revise it in most areas is to actually hire by merit, rather than by university "brand".
A group of people with one gender and color of skin from the same country (to be less US centric) will often have little diversity in their ideas. But just by making sure to have x% of non-white employees you won't necessarily reach that either.