I might be stuck in American!
I am an immigrant, know and interact with people from several countries, and I'm not interested in any combination of clock, date and language, as defined by any one country. This is the internet, after all. I'm only interested in International Standards.
I want to select my language, the international clock (24hr clock), and the international date format (YYYY-MM-DD) on my profile display preferences or something. With the exception of language, this is defined in the ISO 8601.
Adding a date to a card, for example, is a use case where I'm presented with USA formats which I'm wanting to opt out of in order to avoid the insanity of juggling multiple formats at the same time.
Thanks for reading!