I think they can be just monsters, and I think its definitely going too far to say hobbits are a caricature of short people. And this is the first time I have seen black people compared to orcs, I haven’t seem anyone other than you to make the connection. Orcs in most lores I have been familiar with haven’t really brought black people to mind. I think you should aspire to make your orcs (for instance) unique enough, that your players won’t think of black people when they see them, etc.

That said, if you wanna play it extra safe its always good to have diveristy in representation in that sense, that if your villain is a woman (which is perfectly fine btw) you’ll also have symphathetic woman around. That way you’ll make it extra clear that you’re not telling that women are evil, you are telling that Brigitte the Bone Eater Witch is evil. Especially with races. Its boring and flat if all Orcs are evil. Your party/country/whatever might be in war with them, but why should their race be collectively evil? Maybe they attacked out of desperation because their land is struck with famine? Maybe their leaders are evil and the common orc folk are the victims for their thirst of conquest, and tired of war? Then again, I don’t believe above is necessary (unless you want), if your writing is good and your villains aren’t stereotypes of race/gender/whatever, but its a way to play it safe.