For the most part they did though. It still exists for monsters as a very general indication of their values/likely behavior, but for PCs it's now completely optional, and PCs are what got us on this tangent in the first place.
The closest they've come to mechanical alignment are the Paladin Oaths, and even those are open to interpretation in a lot of cases as far as which alignments they support. Conquest for example is a fairly straightforward LE/LN, and Devotion seems aimed at the stereotypical LG shining knight who defends the downtrodden, but something like Vengeance or Glory could be almost any of them.