Except you do still have to think about time, no matter what… Libraries will help with the really messy details, but even the high level requirements have a lot of pitfalls.

“Simple” example that anyone who’s ever worked on a scheduling application will probably be familiar with:

“Get a list with all of today’s events.”

Well, whose “today” (timezone) are we talking about? Server, client, setting in the user account? Or none of the above, and actually timezone at the physical location of the event, if there is one?

And what does “today” mean, anyway? Truncate the date? 00:00-23:59? Business hours?

And what does “today’s event” even mean? Events can cross midnight… Does an event need to start today? End today? Both? Can events span multiple days?

The fun never ends!

I understand the complexity of time, but this scenario doesn't seem all that difficult. Any user expects (I won't get into what they want) to be shown _their_ day, and they expect it to be local calendar time. You _might_ want to show wee hours events, from midnight to just short of 5am. Apps like Teams do a good job of spacially illustrating time as it matters to you _and_ as it matters to others.