Even just using dates can be a mess. At midday UTC everyone experiences the same date. The other 23 hours of the day, a varying proportion of people are experiencing a different date.
"using dates" therefore works out to "not caring about the time of day" and that reduces to "not caring about the time of day in the same timezone" since the same time of day in two timezones have a ~50% chance of being in different dates.
It really comes down to "does your application need to worry about time zones?" If so, then you probably need to treat this seriously, and getting help with that is good. If not, not.
> At midday UTC everyone experiences the same date.
Afraid not. Kiribati, Tonga, Samoa, and New Zealand might be in the following day - they all experience UTC+13. Kiribati and Samoa even experience UTC+14.
Sure, but I was referring more to the times you actually do just want a date. It's perfect for a birthday, or "this day in history", or any number of other things. Nobody really cares that while it was Tuesday where you were born, it was Wednesday for them.
In some instances, if you really only care about the day something happened, adding a time is just extra details to screw up. But if you do need need a a time, you very well may also need a timezone.
"using dates" therefore works out to "not caring about the time of day" and that reduces to "not caring about the time of day in the same timezone" since the same time of day in two timezones have a ~50% chance of being in different dates.
It really comes down to "does your application need to worry about time zones?" If so, then you probably need to treat this seriously, and getting help with that is good. If not, not.