What do you mean by elaborate? I thought my statement was pretty clear.

From the linked article: "Readers – from the conspiracy theorist to the grammar enthusiast, the student of racial injustice to the sociologist – would have something to celebrate."

If applying the pre-1978 laws to pre-1978 works would cause this celebration, then surely applying them to post-1978 works would also cause such celebration.

For further elaboration - if the contemporary rules were applied, then a work from 1977 would become public domain in 2033 and a work from 1978 would become public domain in 2048 (or 2073). If the pre-1978 rules were to be reinstated today, without backdating, then that 1978 work would still take 70 or 95 years. With backdating, it would become public domain in 2034.