Just as an interesting aside...Every race has a creation myth Orcs being the classic one.
Im just saying if a creature superficially looks, behaves and reacts like a person then it’s probably right to treat it like a person.
Orc originates from Pluto who was known as Orcus at some points. Also the word originally means Hell-Devil at a later point of history, but nowhere close to our current time.
Later it would be called a spectre or goblin like creature or devouring monster...
Those origins don't really indicate that the idea of Orcs were something humanlike...or that even acted like a human, but more of something absolutely and sinister which was full of evil.
IF we are talking about origins of monsters and such.
In that light...ANY monster could eventually be taken to be human like and treated as such.
We see Orcs as we do today because Tolkien took the Term and anglicized it to Orc and created them as a goblin type of creature, but still related them back to their lingual roots as evil creatures.
For RPGs that evolved into D&D which had them again as evil creatures...irredeemably so at first...BUT...with the idea that from means we really don't want to discuss here in general...Half-men or Half-Orcs (also another item from Tolkien) were created. 10% of those could actually have the will and ability to be as other races...or like men...and choose to be adventurers or other things. These Half-Orcs were still implied to lean more towards an evil alignment, but they could choose to be any good alignment also if the player choose to be.
This led to later ideas (especially toward the latter half of 2e) that Orcs themselves could choose to be a different alignment (unsurprisingly one of the more famous ideas of this was from a Drizzt Short story, whose main character is also trying to represent a traditionally evil race as also being able to be Good aligned, though I will add in the way that Dark Elves were related in the 80s...that representation of them of always being evil could be seen as HIGHLY problematic without the history that other monsters may follow, as the symbology should be troublesome to a degree for many).
Come along 3e (and a strong Warcraft 3 influence) and people now feel that Orcs are Good or evil just like men and anyone else...and have their own honor and noble heritages to boot. The Orcs have become civilized.
Looking at that evolution, that could occur to ANY monster...ANY of them. It just takes time and evolution of how people perceive them.
Orcs were originally the ruler of Hell, and then Hell-Devils. Just because something is called a Pit-Fiend or Balor today does not mean it will not be the next Elf or Dwarf tomorrow if we want to actually think about the evolution of monster to Good aligned and intelligent PC race possibilities (and actually, if one used the ideas of Savage Species and such, there may be good aligned Balor PC's out there somewhere today already).
In that light, making Gnolls a Fiend today won't mean they won't have difficulties in relating to them (with the same problems we see with Orcs now) tomorrow.
Just something that occurred to me when someone was mentioning the origins of things.
Edit: and as long as we are pointing out origins...of other pertaining interest...Elves were not originally necessarily considered good either...if we see how orcs are portrayed in Beowulf...you'd also classify elves as being evil right alongside them...
Just something of interest to note...