A 4-minute mile represents the same milestone regardless of the other competitors in the race, not relative to their performance. You can win said mile by a min

A 4-minute mile represents the same milestone regardless of the other competitors in the race, not relative to their performance. You can win said mile by a minute, or come last; if your time is 3:xx.xx, then you've broken that milestone. The decathlon works the same way- the points scoring there isn't relative like Elo is, it's done by performance in an individual event. You don't get any extra points for winning a given decathlon event, there's a scoring scale for your marks regardless of position. The exact same performance will differ in how it affects two players' Elo depending on both players ratings. If all players' ratings were to be 100 points higher with all else equal, the top players ratings would rise as well. If everyone in my Mile runs 10 seconds faster, my time doesn't also get 10 seconds faster. Basically, one record is an individual performance mark. The other is a ranking, which is a different kind of metric entirely. With all that in mind, chasing a world record Elo is still a worthy goal IMO. The competitive chess scene is old and robust enough that it remains a meaningful benchmark, even if it is a relative measure.