I'd really wish I could force ISO format for the date input as the current "platform native" is confusing for some users when the OS use a different language than the web page that is shown.

For some multi-country companies it makes sense to have all admin pages in English no matter the underlying OS language. Imagine sending a screenshot where the OS date format is different from what everybody else expects from an English page.

I'd be okay with regional date format for the user but it always submits as ISO 8601 date format.