President Lyndon Johnson said

>If you can convince the lowest white man he's better than the best colored man, he won't notice you're picking his pocket. Hell, give him somebody to look down on, and he'll empty his pockets for you.

It does not just apply to dynamics between white and non white people, it applies to all people, even within tribes of the same skin color, and probably even other tribal species.

He didn’t make it up either - the French government did exactly that about 200 years ago in Haiti. They introduced apartheid for the purpose of sowing discord between people and undermining the independence movement.

An even older example is Indians and the caste system. I would even posit it greatly assisted Britain in being able to pilfer the subcontinent from halfway around the world with a fraction of the population.

Why would all social classes be the same in motivations and goals? You can never trust the "loyalty" of groups they never signed up for.

A mining company owner, a wall street trader, a tech start up millionaire, a head partner of a law firm and old-money heir(ess) would all have different interests and goals. The same goes for lower classes as well.

For starters, the rich have uniform interest in taxation policy - brackets, inheritance, wealth tax, loopholes, trusts, offshores.

Uniform interest perhaps, but decidedly not uniform motivation and goals on those topics.