The best way to overcome the problem of corporation hoarding copyrights and patents in libraries, not using them, but not allowing others to use them, can be overcome with a change to the law.
Make copyright and patent law like the original US Mining law, the General Mining Act of 1872. It said that about anyone can stake a claim anywhere, but they had to either improve that claim to the tune of $500 every year, or make a profit from mining that claim of $500 every year, or they would lose their claim.
An example is Disney, and their copyright of Mickey Mouse and the movie Song of the South. Mickey makes them millions every year, so they should be able to keep government protection for that copyright. However, they did market Song of the South, but now both refuse to, and won’t let anyone else, either.
So they should lose that copyright.
In effect, it would be a “use it or lose it” law.
If they don’t ever want to sell it, no problem. Just don’t release it for public sale, ever. If someone steals it, then sue them for theft. But once it is out there, its future belongs to the market, and that is the only reason it needs government protection.
Actually, you are talking about two different things here. There are trademarks, and there is copyright. Disney corp has a trademark over the use of Mickey Mouse. Trademarks last forever, as long as they are actively used and protected by the owner. Even if Steamboat Willie had mercifully been allowed to lapse into the Public Domain, you still wouldn't be able to make your own cartoon with Mickey Mouse in it. You would be able to share the cartoon Steamboat Willie with anyone on the planet you wanted to.
Many people don't understand the difference, and the media purposefully confuse people about it because they are complicit in the scam.