There's also less nepotistic problems. For example, I've moved between different sides of the same overall field several times. That means, for any given reader of my CV, only about half the "impressive" papers read to them as impressive using most subjective measures.
> Couldn't you just require people to recuse themselves from hiring decisions involving relatives?
They used to have this nice trick where you hired the son of your friend and your friend hired your son. But at least now there are some non-subjective requirements to be met before anyone can get admitted.
Particularly for early career people, I suspect most of these "quantitative" measurements are basically reflecting where and wtih whom you worked.