IMDB has it as 1980. Why do you say 1978? If you're right, we must change it!

https://www.imdb.com/title/tt2238777/

The publication year is cited on the archive.org page. It is indeed 1978.

Maybe some difference between publication and release date?

The description starts with "On July 2, 1978, the last hot lead edition of the New York Times rolled off the presses."

Ok, 1978 it is. I wonder why it seemed like 1980?

IMDB definitely says released in 1980 but I can’t find any other reference to that year.

Everywhere else online says filmed in 1978, including the Times website itself: https://www.nytimes.com/video/insider/100000004687429/farewe...

I’m gonna tell myself they filmed it in 1978 and released it to the public in 1980.

The copyright claim at the very end of the credits (about 28:38) says 1980.