The trouble with technical skill is that you can't measure it with anything like an ELO rating, and it's not easy to prove that knowing a given bit of technical

The trouble with technical skill is that you can't measure it with anything like an ELO rating, and it's not easy to prove that knowing a given bit of technical trivia really helps you be productive, or that a given non-technical skill or trait really doesn't help you be productive. If you hire chess players based on individual performance and regardless of group dynamics, then an argument could be made (not entirely trivially in all cases but it could be) that looking at anything except their ELO is illegitimate bias (and in fact some famous players from Lasker to Korchnoi said themselves that it's this objectivity which attracted them to chess). With programming, or most professions involving something meaningful as opposed to a measurable but pointless (and usually measurable because it is pointless) activity aka sport, it's much murkier.