As for processing, I know the histories of some of my films. Most were bought between 1972-1986.

I have films from WRS lab that look OK and are not stinking.

I just sold a feature from 1977 that had turned brown that Movielab in NYC did. It was not stinky either.

Foto-Kem prints are OK smelling, and have fair color.

DeLuxe prints are red and smelly. I chucked several about 3 months ago.

MGM Labs prints generally turn brownish colored. No vinegar yet. I have a 1971 35mm print by MGM that still looks nice, though slightly discolored, and no smell.

I only mentioned these labs because the prints I bought were brand new at the time.

The TV companies used to treat their prints with something that was so strong that it would bleach the ink off of the labels. Some of my IB prints were treated, and one is beginning to smell. My 35mm IB stuff is untreated and has no smell.

I have a Technicolor lab print of a 1983 LPP feature that is reeking from vinegar. I try to run it regularly.
It came from a depot in Dallas and my guess is that it was a hothouse.

I believe Anscocolor was simply the Agfacolor dye-coupling process renamed when it was used in the US after the War.