One other aspect I think it omitted, likely to balance brevity with scope, is about standard deviations.
When you only have the most rich and privileged doing a sport (e.g. travelling to summit mountains) the "best" will be selected from a relatively small pool of candidates. As an activity gains popularity, and as more people have the means to pursue it, the pool of people for "best" grows and it's no surprise that the max of the distribution increases.
There world's population has grown 2x since 1957 when El Capitan was first submitted. The number of people doing fitness in their free time, I'd suspect is up 10x or 100x. This is double true for activities like Chess or Olympic sports where nation states have started searching for talent in wider and wider ways.