I just checked my copy of TGTBATU, which came from Amazon, and it DOES have some very light oily residue inside the case. Almost like a film. It has not invaded the discs, but I swapped the case out anyway.
I've done some very preliminary comparisons this afternoon, and it's easy to see that (no surprise here) the streaming 4K version (iTunes via my ATV4K) does NOT include the changes that KL implemented for the 4K disc release. The disc is definitely less yellow and definitely exhibits some black...
Based on those screenshots it looks like we're trading toned-down yellow for loss of shadow detail. The crushed blacks are quite apparent. Sigh. I would LOVE to see this great film get the proper treatment that it truly deserves. At 63 years old, I'm hoping that happens before I lose my good...