Apple Intelligence says not available when Mac is set to English (Australia).
Apple says my M2 Mac Air, Sequoia 15.1.1, plenty of HD space is on a waitlist for when it's available. I get this response even after changing from English (Australia), where I had a message that AI was "not available when Mac is set to English (Australia)" or to English (UK). Only changing to English (US) got me as far being put on the waitlist.
MacBook Air 13″, macOS 15.1