If there are two items on the shelf X and Y, such that (< (best-before X) (best-before Y)), then you know X is the older item.
A jar of peanut butter that is best before January 2025 is one month older than one that is February 2025. Therefore, of course, you want to grab the latter one.
Whether it's actually good until February 2025 is just someone's opinion.
Furthermore, if you know that X is a month older than Y, then you know something else: X is at least a month old, today. If you buy the January 2025 jar of peanut butter, you're getting something that was already around for a month when the February 2025 jar was just made, assuming they keep the best before offset the same between runs. And then add the time it took for the jars to arrive to that store shelf.
I would much rather see "date packaged" on every product.
For instance, roasted coffee beans are not very good past only two or three weeks, but not in a way that you would get sick from consuming them. (You can keep them in the freezer to keep the flavor a bit longer.) The exact roast date is important, which they often don't want you to know, substituting a fictitious best before date which includes a generous margin regarding how long it's going to sit in warehouses and on store shelves.