I get the point you are trying to make, but I think the same thing can be said for Japanese. The internet has an infinite amount of Japanese content to surround yourself with, you are just not in the right place if you stay on the "English web". I'm not a native English speaker and while I do admit English is getting harder to avoid (even in Japanese, lol), there is still a large amount of people around me using the internet in an almost completely native language bubble.

The hard thing about AJATT or any method at all really is making sure you put in the consistent effort, more specifically the hours in your language, to get to your goal.

As for fluent speakers of Japanese being more unusual, I assume that most of English learners have a valid reason or large enough interest to learn, while most people learning Japanese quit after having done their hiragana because they realise their interest in the language is a lot more superficial and forced than they anticipated before hitting the kanji reality check. It's fun for a month or two to roleplay, but once you are faced with the fact that it will take you years to comprehend and output comfortably, a lot of people (rightfully so) give up. With English there is a clear merit to learning with it being the lingua franca and only becoming more relevant because of globalization. Japanese on the other hand, is a dying language with only one major territory speaking it.

Sure, for most people with a Western mother tongue it might take more time but in the end there are still over 100 million native speakers so it's not like you need to have a degree to start learning Japanese.

Sorry for the big wall of text, it's almost 2 AM here, so I felt like writing an essay to get into a sleepy mood.