Rather than going in to details why that doesn't matter, with relation to monopolistic power, I'll just let you extrapolate your reasoning to the following:
The EU population is quite literally a minority of the world population.
The EU population is quite literally a minority of the world population.
Meanwhile the EU—a minority of the world population—levies fines based on global revenue.
Another reason the fines are based on global revenue are to get around all the income shenanigans tech companies play, or do you really believe google's most profitable country is Ireland?
>Apple has less than 30% market share globally.
The EU is less than 30% of the population globally, and only 10% of iphone sales. By your logic clearly what it does doesn't have an outsized effect on apple that needs to be corrected.