Direct quote from the page:
Please note that this site is only about US law; the copyright terms in other countries are different.[2]
On January 1, 2026, thousands of copyrighted works from 1930 enter the US public domain, along with sound recordings from 1925. They will be free for all to copy, share, and build upon
Worse, unless you have the source code to that 70 year old software it’s probably even less useful.