This is precisely why the EU is desirable, the biggest country in the union is Germany i believe, if it had tried to do this alone and the likes of google, apple and amazon etc disagreed, it'd only lose ~100m customers potentially.
Now imagine 500m customers instead, that's a much bigger loss of revenue, the problem for google and amazon specifically is that their customers are far more important as vehicles for revenue generation, so no we can't really fine these American companies, but we can sort of do it by threatening to reduce their revenue by such a huge chunk, that they have no choice but to fall in line.
China is even better at this because of it's size and singular direction, Google can't even penetrate it and has tried various times, so it's other markets are ultimately more important, because they have markets that they can't even enter.