https://html.spec.whatwg.org/multipage/forms.html#date-and-time-state-(type=datetime)

Because there is no implementation now though Presto Opera had it.
We don't have a plan to implement it in Blink.

Presto: All input types were supported.
Blink: datetime is not supported.
Edge 13.10586: datetime is not supported.
Mobile Safari: datetime is not supported.
Mobile Firefox: month, week, datetime, and datetime-local are not supported.
Desktop Safari: date, datetime, datetime-local, month, time, and week are not supported.
Desktop Firefox: date, datetime, datetime-local, month, time, and week are not supported.