The recipe of coke is not a copyright, it is a trade secret. Trade secrets can remain indefinitely if you can keep it secret. Copyrights are "open" by their nature.
I was agreeing it could last a very long time, even longer that copyright. But specifically because it is not copyright. But as an AI model, it just won't have value for very long. Models are dated within a 6 months and obsolete in 2 years. IP around development may last longer.