Countries like Australia have always had usage capped Internet, haven’t they?
Yes, but countries like Australia rely on expensive backbone connections. Australia’s main link to the rest of the Internet is via San Francisco, a distance of over 11,000km. That’s where they connect because Australia is an English-speaking country and they want English-language content. In contrast, chances are that if you’re an English-speaking American, almost every web site you visit on a daily basis is somewhere else in the mainland USA, or occasionally in the UK. If you want to compare Internet prices internationally, you should remember that the USA has relatively slow broadband (on average). People in Japan might pay more, but their connection is 10× faster too.