I'm sorry but I don't think 'classic rock' has a period. You trying to tell me that Chuck Berry, Elvis, Jerry Lee Lewis etc aren't classic artists? There is modern rock and classic rock, modern is today, classic is all the best music from all of rock history, which is the latter half of the 20th century.
Guns 'N' Roses had a significant impact on rock history 15 years ago and some of their stuff is classic rock, in 2040 do you think people won't label it as this? It is ever changing. By the way 'oldies'?!?!?!? I thought this was a Britney-free environment, you sound like 12 year olds people!!