Same goes for goblins. They're born with black hearts. Their culture doesn't make them that way - their souls were claimed by their dark gods before birth. They are all lawful evil because their gods are all lawful evil
Basically, I disagree with that interpretation. I'll raise you Volo's Guide, which went into Goblins in depth, including the cases and situations where individual goblins might strike out from their tribes and seek different or better lives. Their individual souls are only sometimes commanded and collected by their deity by force - they are not universally foresworn and forsaken, just heavily dominated. They are socially and culturally evil, and thus the vast majority of them - certainly the vast majority of goblins that adventurers may encounter, will be thus, but they are not intrinsically evil - A creature that is intrinsically evil ceases to be the creature that it is if it ever stops being evil - Devils, for example, if they become non-evil actually physically cease to be devils and find themselves transformed into other creatures. This is not true of goblins, simply because goblins are not, in truth, intrinsically evil. The vast majority are; but not all.
Sure, trusting a goblin you meet on the road might be a bad idea - but *most* of the characters that I tend to play would rather be tricked by an evil creature that they gave a chance to, and deal with those consequences themselves, than to pre-emptively murder an innocent person out of the assumption of evil intent... wouldn't yours?
