He was great among high school runners.
But Ryun and Lindgren were competing internationally as high schoolers. That seems to be of greater significance.
Much easier to compete internationally as a high schooler when there are NO paid professionals, almost NO African participation, and everyone beyond college age is forced to balance training life with a full-time job. You may as well compare Ryun and Lindgren's international performances to Verzbicas' World Jr. Duathlon and World Jr. Triathlon victories, because that's how pitiful the depth of running was back then.
Forget the competition. Ryun was sub-4:00 and an Olympian as a junior. Ran 3:55 as a senior. The distance is the same. Time is measured the same way in 1964 and 1965 as it is today.
And Ryun ran those time on cinders.
Ryun was simply faster, and thus greater, than Verzbicas.
And I would contend that Ryun’s 3:55 on cinders is a greater performance than Webb’s 3:53 on an all-weather track.
And Webb is greater than Verzbicas.
First things first. Being an Olympian back then is not a particularly compelling point, given the post you're responding to. I'm not sure about the depth in 1964, as it was over a decade before I started following the sport, but no one can deny that the depth in 1964 was most definitely inferior to the depth in 2010+. In that respect, you can't argue with the post you're responding to.
What Jim Ryun DOES have is an exceptionally fantastic Mile time. However, there are more races than just the mile. Assuming we are discussing high school DISTANCE running, this ranges from Mile - 5000m, and also includes cross country. In this case, we'll operate under the assumption that the 1500m and 10000m are not run commonly enough to really have an impact here. Additionally, to make this fair, since we are not considering Ryun's international performances based on lack of depth, we will also eliminate all of Verzbicas' event-related accolades (2 x FL championship, NXN championship, NBIN Champion, etc.) since Ryun did not have events of that nature back then. This leaves us just to compare individual events. Without a doubt, Ryun is superior in the mile. However, Verzbicas is better when it comes to Cross Country, the 2-Mile, and 5000m.
To be honest, I don't know what Ryun's 2-Mile/3200m time was in high school, nor do I know what his 5000m or Cross Country times were. What I do know is that they were not remotely close to Verzbicas' 8:29 (outdoors), 8:40 (indoors) and 14:06 (indoors). Moreover, Ryun's 3:55 is good, but the margin by which he is better than Verzbicas in the mile (3:55 vs. 3:59), is just not enough to make up for his inferior performance in every other relevant distance event.
Concerning Webb, he has a much better claim than Ryun, given that he has a better mile time (3:53), and actually has passable cross country and 2-mile performances. However, his cross country performance is significantly worse than Verzbicas, and he still loses out significantly in the 2-Mile and 5000m.
Verzbicas wouldn't be considered the best high school Miler, 5000m runner, or XC runner. He would only be considered the best high school 2-Miler (regardless of any protests by Lindgren). He WOULD be considered the best high school distance runner overall, because among all high school distance events, he has an exceptional performance in each.
Cross Country: 2 x FL champion, NXN champion.
Mile: 3:59 (while being rained on)
5000m: 14:06 (i)
For those latter 3 events, he also won the NBIN 5000m, 2-Mile, and Mile in the same meet, and won the team national championship by himself.
No one high school athlete greatly exceeds Verzbicas' performance in any one of these events, with the exceptions of Webb in the Mile, and Rupp in the 5000m. For any one of them that can beat him in one event, they almost without exception lose out to him significantly in every other event.