This is trying to treat the symptoms, not the disease. You yourself say "they tried for months and were still unsuccessful at finding a single one". Why do you think that is?
Whatever you're trying to solve - the "issue" starts decades earlier, at home. It's about how people are brought up, their access to education, their social environment. Culture actually plays a role, too.
When it comes to a recruiting pipeline this is critical. If you are tapping members of your team to help finding candidates from their networks and your team lacks diversity, you are going to just build out your team with more of the same.
The same goes for where you are looking for candidates outside of your team. If you are only targeting a small number of schools it's really easy to end up with a homogenized set to pull from. I know from experience working at some of the big tech powerhouses, they'd target a handful of schools and only hire college grads from there - which means they miss out on recruiting from state schools, historically black colleges, and other pockets where things are more diverse.
What conclusions do you draw from this? That "people are racist"? That the pipeline is broken? This feels like ignoring the elephant in the room.
I think it explicitly said they did not do that:
> I spent months waiting for a single person to apply who fulfilled the racial requirement. When no one did, I spent hours trying to find people on LinkedIn who I thought might count as black or Hispanic based on their name or resume.
It seems like a good next step would be to give the author more tools to find more diverse candidates, rather than having them come up with trying to gauge ethnicity by name on LinkedIn and getting those to apply.
I'll chime in here that if a person works at Microsoft and has the resources of Microsoft recruiting on their side, that they are in a better position than most to end up with a wide choice of applicants. Microsoft can sponsor visas if need be, and their compensation is generally high enough to merit consideration of relocation, if necessary. (Worth noting here that a non-diverse slate of applicants is in many cases a process smell that your pipeline sucks.)
We also don't know for what role(s) the author was hiring. While the assumption here seems to be that they were having trouble finding a diverse slate of applicants for "Senior AI Researcher, PhD and 20+ years experience required," for all we know they are whining that they couldn't get applicants to be CRUD programmers building out APIs, or PMs, or doc writers, or any of the other myriad roles that go into shipping software. Given that, we don't really know where to place blame. Could be that this manager just sucks at their job.
When I'm troubleshooting a bug, the first thing I do is to enumerate the possible ways in which the bug might occur, then devise tests to rule out most of those possibilities. This doesn't seem to be any different.