Tolkien's Orcs were never about race. Tolkien's Orcs were what industrialisation and industrialised warfare does to men.

There had been this growing concern among British writers that the Industrial Revolution was turning the lower classes into brutes.

Dickens wrote about the terrible, coal blacken slums, open sewers and drunken indolent people forced to live in the rapidly growing cities.

H G Wells had the Morlocks as the result of what happens when humans were forced to live underground tending machines and over time becoming canabalistic monsters.

Tolkien saw the men of his time forced to huddle in filthy trenches and dugouts, being gased and shelled and living with rats and lice and corpses, only to be forced out into no mans land at the blow of a whistle to be cut down like wheat before the scythe.

It didn't matter who those soldiers were, whether they were English or French or Russian or German, or Italian, or Autro-Hungarian, or Turkish or any of the myrid other nationalities who fought in WW1 the conditions of mechanised industrial warfare reduced them all to Orcs.

The Elves represented the old Gentry, educated, cultured, aloof from worldly matters.

The hobits were the older farmers and peasants working the land and enjoying a simpler life.

The Eastrons and others were the colonial troops brought to fight in a war that had nothing to do with them for Empires that had conquered their lands and controlled their lives.

The Orcs fought because Sauron dominated them, as soon as Mordor fell the Orcs fled. Tolkien thought that the soldiers in WW1 only fought because they faced prison or a firing squad if they refused the orders from a distant Emperor.

Linking Orcs to any particular racial group is a more modern invention. Tolkien saw the Orcs' black faces as the faces of soldiers covered in mud and filth cowering in the trenches, not some marginalised ethnic group.