There's no central authority for scripture or Christianity, your individual faith defines your morality

We can be very narrow and go to the solae, or demand that it be only those movements that arose from the protestant reformation, or we can be very broad and say that it is any branch of western Christianity that is not Catholic. Protestantism can have an extremely centralised authority over what defines acceptable christianity, in fact it can even have a state be that authority and enforce it by violence. Anglicans and Lutherans generally have centralised and hierarchical authorities dealing with matters of doctrine.

The most American branch of Christianity is mormonism, and mormonism isn't even protestant except by the widest possible definition.

What you want to talk about is the Matt Christman warped take on protestant work ethic (Itself a deeply flawed, unmaterialist and supremacist viewpoint written by protestants to jerk themselves off about how great protestantism is) and how protestantism is the source of all America's ills because it created capitalism and American consumer culture. Which it didn't.
But also nominally Catholic America has the same brain worms, as do nominally Jewish Americans, as do nominally Muslim Americans. America has a civic religion and that religion is not protestantism. It is greatly influenced by protestantism, certainly but this a temple American consumer culture built by Americans for the splendour of America and the American civic religion can be celebrated there by all despite their nominal creed. Jew, Muslim. Catholic, Hindu, pagan, atheist all can worship the rodent and the almighty dollar.