If anything people in the US should be glad the EU is doing this, since it might also benefit them in the long term.
It probably started with public companies not paying dividends and instead rewarding the shareholders by share price increases.
This means they have to grow indefinitely. The logical outcome is having one all-encompassing monopoly that handles everything. Kinda like a state economy, but they don't get the irony.
... that actually tracks pretty well.
Unregulated free market capitalism that so many people seem to root for (knowingly or unknowingly) is just a degenerate version of the system that invariably results in cartels, price-fixing, rent seeking, thought policing, human exploitation and suffering, which is really just a different version of the "communist" boogeyman that they fear for the same reasons.
Heck, limited liability corporations can only exist because laws make them possible.
To be clear, fining is not stealing except in some kind of liberal dystopian fantasy.
And fining based on global revenue is necessary because it's all too easy otherwise to artificially shift revenue between various places to evade these kind of fines.
The fine is limited by law to 10% of global revenue, and the EU market is more than 10% of Apple's revenue, so there's nothing particularly egregious here. Also, obviously Apple is not forced to do business in the EU if they don't like the rules.
Many countries have fines relative to the income of the perpetrator. If you get caught speeding as a tourist in Norway do you expect to get away without having to pay anything since you don't have an income in Norway?