Well, the EU has about half a billion people, India and China about 1.5 billion people - all larger markets (by headcount) than the US domestic market, so nothing that any American company can just choose to ignore.

Either of these three markets can set rules on what device manufacturers have to do in order to be allowed to access the market, and they all use that power - China is particularly infamous (with Apple having had to set up a dedicated iCloud instance to which the Chinese government may or may not have a backdoor), India more focuses on the share of production that happens in China, and the EU is seriously tightening the screws on American companies when it comes to arbitrarily denying store access.