I don't know that the milk comparison is really a good one.
Milk reaches a point where it definitely goes bad. I know only a few insane individuals that will drink milk after it has started to curdle, and most of us have a point well before that, that we won't drink it. It seems that the change, from fresh to spoiled, is on a curve. IDK for sure. Perhaps we have someone here that does?
Motor oil on the other hand, really has no expiration date. Except for the inconvenience of fallout of additives, I don't know of any real disadvantage of using 4 or 5 year old motor oil. I haven't seen anyone here report that they had to replace rod bearings after using old motor oil. I vaguely recall Blackstone Labs running some testing on some very old motor oil, and even ran it in some older engines, for which the oil was spec'd for, with no bad consequences.
This isn't the article I'm thinking of, but here is one where Blackstone tested some 14 year old M1, and found it still meeting specs.
https://www.thedrive.com/news/motor-oil-age-doesnt-matter-as-much-as-mileage-study.
Is it good to be using 15 year old motor oil? Perhaps it might be wise to not do any extended runs with it, but from what we read, it will still work. Is motor oil that just hit the shelf going to protect an engine any better than some that has been in a stash for 3 or 4 years? Nothing we have seen here shows anything to support that theory.