I dunno what the patent duration is, but copyright should probably just be 50 years max IMO. If you can't make bank in that time without changing the idea up (and thus getting 50 years on the new version) you don't deserve it.
Originally I think it was closer to 20 years. Frankly I think 25 years is plenty. A quarter century is enough time to reward the creator of an IP and it respects the fact that all IP is built on top of the public domain so it's return is a natural part of the cycle.
In any case it's not like after it expires you could not trade on being the original. It's not like others could then come along and claim to have been the original creator. And if you kept making works those would each get their own period of copyright.
I dunno what the patent duration is, but copyright should probably just be 50 years max IMO. If you can't make bank in that time without changing the idea up (and thus getting 50 years on the new version) you don't deserve it.
Originally I think it was closer to 20 years. Frankly I think 25 years is plenty. A quarter century is enough time to reward the creator of an IP and it respects the fact that all IP is built on top of the public domain so it's return is a natural part of the cycle.
In any case it's not like after it expires you could not trade on being the original. It's not like others could then come along and claim to have been the original creator. And if you kept making works those would each get their own period of copyright.