Asklemmy

Like others have said, there is a big confirmation bias: you speak English and use platforms dominated by English-speaking countries. Your view of The Internet is limited, as is all of ours.

(I'll try not to just repeat other points, there are many excellent ones made already)

I assume by 'western' you mean USA, Canada, UK, etc., which are primarily English speaking as a primary language, rather than many European countries with it as a common second language. They often have their own national-language sites and forums, which obviously won't be as big as the English-speaking ones which is able to be used by more people. Many even just hosted them on language-ambiguous platforms like US social media giants because its free and people are already there.

Additionally, USA holds an important international position at this point in time, especially in terms of pop culture, cinema, music, politics, news and technology, so US sites will probably have a lot more global appeal than, for example, Chinese sites.