It's his opinion not an argument. He thinks how the older generation have been treated is grossly unfair and thinks that cortese will eventually sell for a big profit. He also predicts insults for expressing that and sure enough out they come.
Whilst I do not share that entire opinion, I think it's totally correct that he is allowed to express it without abuse. There is no argument here, just a fellow fan expressing an opinion which differs from the collective 'opinion' of the forum.