it's not at all like Wimbledon
Congratulations on missing the point.
Is there a veteran Wimbledon? Do you ever see the England over 40's football team on TV. Who is the World Masters 100m champion?
My point is that Juniors Elites are treated like Senior Elites, because in a few years they will be senior elites, they are on the way up. Veterans are on the way down.
Juniors and 35's are to be expected to be at the top. 18,20,21,35 should be one course, not age-class, in sprint, middle and relays.