this wont happen. with specialization in the pro peloton, I doubt any rider will ever again have palmares that read winner of MSR, Flanders, and the Giro GC (or any GT GC) in the same season ... or in a career for that matter. they're just too different.

like almost any sport, comparing athletes from different eras is silly. reasons: specialization, trade teams vs. national teams, prioritizing races based on global marketing exposure vs. purse size and historical significance, bigger $ in the sport, etc., etc., etc.