If most Metal festivals have a hard time grabbing a foothold in the U.S., then there is now way in hell that a classic Hard Rock fest could be successful. The average person who would even care to attend would be around 45 years old, and that would be even hoping that they WOULD go. Most of the people who like that stuff are not really the concert going types anymore.
45 seems a bit excessive; I'd say 37 and I'm not even close to that and would go see the Firefest concert in a second were I in the UK. Tyketto was possibly my favorite late 80's hard rock band and I did at least get to see them once in 1993. Forever Young is one of the greatest hard rock songs ever devised.
That said, hard rock has pretty much no presence at all in the US and I doubt a single show could be viable, but then again, how viable was a prog metal / power metal show in 2001? Probably still a little more viable, though.
Prog and power metal are developing here slowly but surely, at least as far as the fact that I will be seeing Edguy and Symphony X at the House of Blues (Anaheim) this year, whereas I saw them at the Galaxy, a local club with the dinner-theater setup going, the last time each came through. It is definitely a step up, although I do not know the occupancy figures on each building. Kamelot and Sonata are still at the Galaxy though. Nightwish was at the House Of Blues in 2004 and 2007.
I think the type of metal that they play on Headbanger's Ball 90% of the time (that I cannot begin to listen to) and at Sharon Osbourne's traveling show is many, many times more popular in this country, though. Although we have reached the point where we have several prog/power tours this summer and fall, it is still just in clubs. Hard rock bands can tour clubs if they were famous back when hard rock actually got airplay (Metal Mania bands) (I tried to see Tesla at the House Of Blues when I was buying my other tickets and was very surprised to learn it was sold out) or they can group up to do amphitheaters, but there does not seem to be any avenue whatsoever in America for new hard rock bands to be noticed.
I think the prog/power situation is pretty ideal right now - I can see my favorite bands every year or two for twenty bucks and get right up to the stage if I want to. I can discover some new bands from the opening acts (unless it is Into Eternity AGAIN) and from going to PP. The only thing I would change would be that every summer there needs to be a tour of Circle II Circle, Jon Oliva's Pain, and Chris Caffery, and every show ends with two hours of songs that predate those three bands.
What hard rock would need to do in America is have the older bands find some newer bands and use them as their openers instead of using less famous older bands, but then again the average person going to the show probably would prefer the less famous older band and might not have any interest in any new bands. They're never going to get airplay, but I don't think Nightwish, Edguy, or Symphony X ever did.
Now I seem to be reaching the conclusion that maybe someone does need to break out a hard rock version of PP, but I would still say that PP bands had much more of an audience (especially in terms of people that would go to see a concert and TRAVEL for it) in 2001 in the US than new hard rock bands do now. You can't use older hard rock bands to headline and get the building filled because people can see most of them touring already and aren't going to travel for it, and anything special would just go on a big tour (Van Halen bringing Sammy back and the aborted return of Diamond Dave, Axl and his debacle).
Hopefully there is a point or two buried up there somewhere.