Yuri

brazil has the biggest japanese population outside of japan and we dont speak spanish x

didnt know english was a flop language

... what

Let me explain more in depth. 

One: While English is definitely widely spoken, not all the English speaking countries are as closely connected (IDK if that's the word I'm looking for) as Spanish speaking ones. I was more getting at how it's easier for something to spread within Spanish speaking communties than English ones.

Two: I said ALMOST all of South America. Obviously I know Brazil speaks Portuguese. So please read what I say.  

Three: While English is definitely an official language in many countries, let's be honest, they're not as closely intertwined (IDK if that's the word I'm looking for either). An Argentinian is more likely going to be in the same online community than a US citizen and a person from India. English speaking communities tend to me mostly US, British, and Scandinavian (Because for some reason, a lot of Scandinavians speak English).  

I'm bad at explaining stuff, but I hope this clears up my original comment. 

Also, my entire point here is speculation anyway, as the real reason could be much different. I was just providing a possible reason.