In article , says...
Color film? I didn't know they even made color film 40 years ago.

Sorry, I forgot to put the irony indicator into my post: irony or ;-)

But while I'm mentioning it, most color films of the 1950-60s (except
Kodachrome of course) were much less archival than those of today.

There are a lot of variables here, storage being the main concern. I have
seen good results from films over 20 years old. How they were stored I
can't tell you but it is not always a loss or worthless effort.