Define 'success'? Financial or something else?
Yes people do want their work appreciated. I dispute the fact that anyone makes something today based on the financial worth of it 70 years down the road.
Pointing out examples that just so happen to have lasted a long time doesn't mean they made it with that expectation.
Further if that is provably the case, you still have to answer why they have a right to a state sponsored monopoly. And after all that my second suggestion is to have an annual increasing fee. So that only things that the owners are willing to actually make use of and pay to maintain stay copyrighted. That would seem to answer your objection
Houses of the Holy is 50 years old. So is Innervisions. There's A Riot Goin' On? 52.
If you're trying to argue that success at the scale of Zeppelin or Seinfeld isn't somehow an incentive to creation, I mean, OK, but I guess I can rest my case, too.