Earlier quoted context omitted.
I've liked the suggestion of an increasing annual cost, perhaps double, every year past a certain baseline - so if the work is valuable enough, productive financially, then the owners can afford to retain/maintain full control over it.
This would just mean that rich companies/people will get to keep the copyright and others do not. We're in this whole situation where things don't enter the public domain for 100 years because of Disney's lobbying.
Also, I often advocate this, and to some extent I consider it a strategic retreat. Fine. You're a big company and you want to own your stuff forever. But behind the laws protecting those companies there's a ton of stuff that the owner doesn't care, nobody even knows who the owner is, etc. etc. (There's a lot of stuff that is de facto in the public domain because nobody owns it anymore in any practical sense, but there's no way to be sure what that stuff is, and the risk is too large to take.) The stuff the big companies are defending is just a small fraction of what exists. If we tuned the laws to give the big companies what they want (more or less) but stopped protecting everything else it'd be a win. And they can pay an increasingly steep fee for the benefit.
Or, to put it more prosaically, I don't really care how long Steamboat Willy stays under Disney's copyright, I'd like Steamboat Willy to stop shielding everything produced ever.