i don't think i'd consider him number 1 all time. lets look at it.
Ritz faced stiffer competition and won 2 XC Championships. He also got the Bronze at World's. LV won 2 (yeah i know he won the team thing too but that hasn't been around for that long, winning 2 XC titles in one year just shows that you are the best XC runner that year, doesn't really add much prestige when comparing top HS'ers ever as far as i'm concerned). So purely XC i'd say Ritz is best with LV probably 2nd best.
Mile - Since LV went 3:59 in a HS race i'll put him clearly above Liquori and Danielson. So he's definitely 3rd best Miler ever but still FAR behind Ryun and Webb.
2 Mile - LV has the record. The one thing to consider is Webb ran 8:44/45 all alone indoors (Brannen was never really in it) and dropped 6 seconds in the mile that year from indoors to outdoors. If Webb had run the 2 Mile late in the Outdoor Season the 2 Mile Record would probably have been sub 8:30 for the past 10 years and I'm not so sure LV would have it now. But thats a hypothetical so we'll never know either way. LV is the best, while still keeping in mind that Webb didn't run it and had a very real chance of running faster than LV.
5k - Rupp has the record and it is about 30 seconds faster than what LV ran indoors. That is a lot of time to make up from indoors to outdoors. It's possible though. So just like in the 2 mile we don't know if Webb woulda put the record out of LV's reach, in the 5k we don't know if LV coulda beat Rupp's record.
I don't think it is entirely fair to say that people like Ryun and Lindgren competed with the best in the world so they can never be touched by current athletes. That was a different era, an era in which it was possible for a freak High Schooler to match the international elite. Thats just not the case anymore and I don't think it ever will be again. The great thing about track and field is that the times spell it all out in black and white. Granted, tracks have improved a lot since the 60's so that does make comparing the athletes of those days with today's athletes a bit harder. But to make it easy lets take the old athletes out of the equation and just focus on modern athletes (i.e. the fastest runners in HS history)
I could care less about German being young because this is about what they did in High School, it doesn't matter what German did when he was finally 18 and had a bunch of months of college training. LV defintely is over German cuz he has a faster mile, 2 mile, and better in XC. LV is definitely better at track than Ritz, although not as good in XC. LV is definitely not as good as Webb in track who ran 1:47/2:24/3:53/8:44i. LV does beat Webb in XC. But nothing LV has done comes close to a 3:53 mile which is easily the best time-performance in high school history. 8:29 doesn't touch 3:53. LV does have the best championship record but outside of having to beat Cheserek a couple times he didn't have to beat guys anywhere near the level of Webb and Hall for Ritz and of Hall and Ritz for Webb. There are also more championships available to win now (2 XC's a year, 5k indoors) so its not fair to just say LV won more national titles. If there had been two xc titles in 2000 Ritz woulda without a doubt won them both and maybe would have won them both in 1999 as well.
In terms of just modern day athletes I'd say: