Practically speaking, copyrights are perpetual in the US. If something is copyrighted for life plus 90 years, I'm not going to see anything made during my lifetime enter the public domain naturally.
Even as recently as 1998 copyright was only authors life plus 50 years, and less before that.
Practically speaking, copyrights are perpetual in the US. If something is copyrighted for life plus 90 years, I'm not going to see anything made during my lifetime enter the public domain naturally.