No one has ever been able to explain to me how “not inherently evil” = “humans with (insert flippant descriptive element)”
If Alignment is the issue, that's already been covered though. It's not applied to PCs.
Having a culture that doesn't mesh with its neighbors is fine.
Other than (once again) Volos, what's the problem? Not everyone wants a cosmopolitan world. Eberron is fine, for those who want it. Sigil is conceptually fantastic for subverting tropes.
A world where there isn't massive open migration is going to have strong established cultures. Where those cultures originate from matters. If that source is a hateful war god in a world where Gods, and Clerics, and Magic is real, and you could literal find yourself before your God having a conversation?
Well for my money, your going to have a culture that matches that gods ideals.
My Orcs are not savages in furs. They are brutal, organized, prosperous, and supporting of the people they rule over.
They do rule though, they don't accept challenges to that rule, and they firmly believe in their own superiority.
Now is that evil? It's absolutely a brutal dictatorship, but those who live their have peace, and a better quality of life than the human kingdom neighboring them.
Maybe it's evil, but the Orcs don't think so.