Yeah, that's something that I have been a bit confused on too. People talk about how hard it is and the "prestige", but there are 20k+ other engineers who did the same thing (at your company alone!). It's really not all that impressive.
The relevant metric would be the ratio of how many got the position to how many wanted it.
Not really - that would inflate how impressive it is, because the bottom, say, 80% of the talent pool applies to avg 100 companies whereas the top 20% applies to avg 5 companies, so the number of talented applicants to a given company is very small. Just because you hire top 1% of people who apply to your company doesn't mean you hire top 1% of devs (even if your company is getting the best average applicants).