The US is part of the WTO and thus a signatory to the TRIPS agreement ( https://en.wikipedia.org/wiki/TRIPS_Agreement )
> TRIPS requires member states to provide strong protection for intellectual property rights. For example, under TRIPS:
> Copyright terms must extend at least 50 years, unless based on the life of the author. (Art. 12 and 14)
> Copyright must be granted automatically, and not based upon any "formality", such as registrations, as specified in the Berne Convention. (Art. 9)
Changing that to a "short term and renewable" would involve leaving or renegotiating the WTO. That is likely a non-starter.
More kind perhaps but really anything that prevents you as an adult from building on the works that your grew up on is a shitty deal for society.
I think the original terms of American copyright are fine to use as a model: 14 years for all works, period. And certainly that's open for debate; even 25 or 50 years would be much more kind to the commons than what we have now. We could even do like we do for patents, and have a relatively short term, with a one-time renewal option for creators who continue to benefit from a work and still care to keep it protected.
[0] https://www.arl.org/copyright-timeline/