See, I don't think the guidelines need to be fixed. There's nothing inherently wrong with a species that's just evil by default. Fantasy is fantasy, not the real world. Having generally evil races is about having monsters for the party to fight without feeling remorseful. They're stock bad guys. It's not complex, but not everything needs to be - especially for a recreational activity like DnD.
Yes. Let's just play out the same tired Villian archetype of "Me Orc. Me Green. Human Bad. Kill Humans! Rarggh!"
Truly this is compelling storytelling. Using the LotR Orcs as an example, Shadow of Mordor actually made you care about them by making them interesting and giving them an actual character that's not "Me Orc. Me Smash."
There are smart orc, Funny Orcs, Honorable Orcs, Downtrodden Orcs, Orcs who play music, Orcs who have strange a bee fascination.
Sure, if you want to run forgettable Orc fight number 5492, then I can't stop you, or, you can make them actually memorable and interesting. If Villians aren't memorable or interesting, then they aren't good Villians. Orcs almost never slot into that spot, they are all the forgettable meatshield jobbers that only exist in the world to wear you down slightly before the actual fight.
No. They don't have to be well defined, memorable, and interesting, but they should, or you're doing them anywhere near the justice that they deserve as a race.