All this to say that yeah it makes sense that people would learn Japanese over Chinese explicitly because there's more content in that language and that content is also more talked about.

This is also why I'm big on subbing and dubbing anime into a wide variety of languages: if utilized effectively, anime can be genuinely great language learning material not just for its original language but for any language you can think of.

Edit: Obligatory mention of my /c/worldbuilding post about the Open Sign Language Animation Project