Every time people lament changes to the lore that amount to “not every member of species X is irredeemably evil” and claim the game is removing villains from it, I think how villains of so-caleld evil species fall into two cathegories: a) bland and boring and b)have something else, unrelated to their species going on for them, that makes them interesting.
I feel like:
“No villain in D&D is interesting for reasons tied to their species” sounds very dangerously close to “I’m race-blind” in terms of not acknowledging that different people have different struggles, and racism is often a huge part of those struggles.
If you like this idea, you should read the webcomic The Order of the Stick. It’s surprisingly good for a comic that started out as DND jokes and stick figures. It deals a lot with the problem of evil in DND.
Likewise, Goblins.
Your number 2 is based around cultural, not species differences. Two humans raised in two different cultures could end up very different.
There could be two tribes of goblins. One that began eating people out of desperation and now just do it because it’s tradition. The other could have grown up in close relationships with their nongoblin neighbors and are seen as a valuable part of their region.
So untying evilness to their race isn’t being race blind or pretending people down have struggles - it’s removing the shoehorning that occurred.
Big cats have hunting instincts that are hard to turn off even if they like you (see: any news story of a big cat eating their owner), humans have instincts relating to forming communities. every single species has some instincts they follow and they aren’t the same as ours, they’ll deeply shape how a species’ cultures/morals/etc develop. Just saying goblins are little green humans is deeply boring and hurts world building.