The Spanish conquistadors were feudalists, not capitalists. Spain actually had one of the most rigid and statist economies in all of Europe. The sort of tribalism (of the European colonists) that lead to the destruction of native societies in the Americas, both North and South is it's own thing and exists independently of the economic system of those practicing it.
In fact Capitalism says very little about politics though. All it takes for it to operate is a functioning legal system and respect for property rights, and that's about it. Capitalism is simply about the freedom to own and raise capital, make investments and earn profits. That's about it. People have been doing that for thousands of years, it's simply the degree to which it is taken that makes the difference. What makes a system non-capitalist is really the degree to which freedoms to invest and practice economic activity are restricted or reserved, and the degree to which property, profits and investment can be appropriated.
Capitalism has very few ideological requirements. A such you can layer over or under it almost any other political ideology. Just look at China with it's Communist political system, statist public sector but burgeoning capitalist economic sector. Is the persecution of the Uighurs down to capitalism?
One problem with capitalism is that it makes a society dramatically more efficient and wealthy, making it a lot more capable of prosecuting whatever other political, racial, cultural or religious agenda the society might have. Just look at the wealthiest nations on earth. They are either capitalist, or they are resource rich such as the petrostates, or in the case of China have re-branded capitalism as 'Chinese Characteristics' and used it to fund the statist side of their agenda. Russia is failing precisely because it has been unable to establish a functioning capitalist economy and relies on oil and gas money instead.
Look at the middle east. Israel is easily the most capitalist society in the region and, even though it faces up to some of the wealthiest nations on the planet, if there was a war between Israel and say Saudi Arabia even, there's no doubt who would get humiliated. That's how terrifyingly effective capitalsim can be. It's the reason Japan rose from being a miserable medieval backwater to dominating all of Asia, even though it retained it's feudal hierarchy. That's how flexible capitalism is because it's not really an ideology, it's just about basic economics.