Ah, the problems we encounter when trying to accommodate our favourite tropes into something we create.
The original D&D was based more around Swords & Sorcery then High Fantasy, and as such used the Law vs Chaos concept pioneered by Michael Moorcock and later fantasy writers in the 1960s and 70s. Sadly, they did not take Moorcocks' more nuanced stance on character, where action is more often based on personal than philosophical drivers.
AD&D went more for High Fantasy tropes, by introducing subclasses such as the Paladin or Cavalier, and by introducing the twofold alignments (or as I called it, the philosophical/moral system). But when you get into HF, you get into Tolkien, and Tolkien the Catholic believed very firmly in Good and Evil. Be it noted that JRRT never believed in inherent evil. His evil creatures all started out as good (even Melkor and Sauron) but became corrupted as Christians are taught that Mankind did.
There are a few films and books that take the Orcs'-eye view of things. It was always telling to me that Tolkiens' Orcs, especially the more evolved Uruk-Hai, spoke of the Free Peoples as 'rebels and brigands', implying that they believed they were on the 'right' side, serving the rightful Lord of Middle-Earth.
Just FYI, in my fanfiction, The Doctor (Ten) told Harry Potter that the Goblins were descended from the Orcs, who once free of the Dark Lords' influence, built a mercantile society.