Set your iPhone language to “English (Australia)” and then try to type some words.
Realize aluminum color
Those are American spellings.
For a company that obsessively auto capitalizes (argh capitalises) words like “FaceTime” and “Apple”, it’s hard to see this as unintentional. They employ many experts in language and internationalisation.
Someone, somewhere at Apple made a conscious decision to push Australian language more towards the US. They’re culture hacking us.