Particularly for those who believe in immersion-based language learning, it's almost unimaginable how someone could learn a language to fluency in the pre-internet days. The access you have to native material now is a night and day difference.
Not only has our ability to learn a new language changed tremendously, but so has our motivations for learning a language. In the 1950s there would be no real reason for an American to learn Japanese. Many people would probably go their entire lives without even meeting a Japanese person, so what use would their be in learning their language?
Nowadays, of course, that's entirely different. Whether it's anime, manga, novels, websites, etc., there are plenty of reasons for someone to learn Japanese even if they might never meet another person who speaks the language. The internet has put countless cultures at our fingertips, and I think that's pretty cool.