@patrick_h_lauke I had occasion to test this recently (fairly quick tests, there could be other issues):
date, datetime-local, time - using arrow keys to cycle values initially resets them first (when no initial value has been set, Safari shows today), eg. up-arrow from month slot "04" cycles to "01", or down-arrow to "12"; up-arrow from year slot "2024" cycles the year to "0001", down-arrow cycles to "275760". All slots have this behavior.