Some things are good hard, the kind of hard that's driven by an interesting domain, going deep with well-architected tools or systems, learning lots of cool stuff.

I expect datetime-adjacent code is basically the opposite of all of this. All the hard parts are driven by fiddly adherence to real-world geography, politics, physics/astronomy, etc. There's no underlying consistency from which a sane model can be extracted, it's just special cases and arbitrary parameters all the way down.

I'm up for a challenge of course, but all else being equal, I'm happy to leave work that is the "bad hard" to others.