Because they are lazy and are not aware of the prior work.

Already decades ago many have proposed to use only TAI internally in computers, instead of UTC, which is not a time.

UTC should have always been used only to compute the local times, together with the time zones, only for human interfaces.

There have been for decades libraries for using TAI instead of UTC, and even versions of Linux or *BSD kernels patched to do time keeping in TAI, not in UTC, eliminating all problems with the leap seconds.

Unfortunately the use of TAI has remained a niche, but that was the right solution.

Worst part is, the arguments are a bit silly.

Time may change forwards and backwards, because my computer clock may be fast or slow. The same logic to correct for leap seconds, can be used if my computer is 2 sec fast.

And your code had better handle it, and the os, libraries, it really is only hard ), if you have to support 1000s of novice devs.

And FWIW, every major company does have to support a thousand novice devs, every year, over and over, forever.

Honestly, this issue screams education problem. "Time is a mess" should be taught alongside buffer overflow attacks and networking theory (in fact, networking theory is a great place to teach "time is a mess," because you can roll it in alongside ideas like "simultaneous action is a lie" and "clocks are always wrong anyway").

Because time in the real world uses leap seconds. The time businesses open and close. The times reported in news articles. And so on. What facebook wants is for all of them to stop using leap seconds so facebook’s infrastructure is simpler

Times reported in newspapers are not granular enough that it’s even possible to notice whether leap seconds are used.

It's not just Facebook. A large community doesn't want them.

https://www.cl.cam.ac.uk/~mgk25/time/leap/

Time in the real world can use leap hours, the next of which will be in approximately 3000 years.

The article you linked seems to be arguing pretty strongly against leap hours. I'm not sure we could solve all those problems even in 3000 years. Can we compromise and use leap minutes? That way the problem is a bit more immediate, in 50 years we're sure to have solved it; or we'll all be dead and it will be on someone else!

Instead of leap hours we could just permanently abandon leap anything, and state that the offset between UTC and TAI is fixed at 27 seconds from now on, forever. Every few thousand years, when this new UTC has drifted enough from solar time on the prime meridian for people to start noticing and caring, countries can decide to simply change their offset from UTC, which will just be a normal update in the time zone database that doesn’t need to be coordinated with anyone else, i.e. something that already happens quite regularly.

This is all quite hypothetical as it’s hard to predict whether anything like our current technological civilization will exist thousands of years from now, but even if it does, a simple mechanism exists to avoid problems (just have each jurisdiction change their local time when they decide they want to).

I can’t see any downsides for literally anyone from this proposal, other than the insignificant downside to the British that they will lose the prestige of being the place that global standard time is based on.

Yep, either just redefine the timezones-- or perhaps better just issue new "New Eastern time" that is offset by an hour.

> lose the prestige of being the place that global standard time is based on.

You joke, but that's actually a source of some of the opposition. :(

Brit here.

It infuriates me that the BBC World Service insists on announcing the time as "<something> GMT", pronounced in a smug tone of voice. The GMT timescale no longer exists; nobody broadcasts it. What the announcers are broadcasting is the BBC's ignorance. I find it embarrassing and jingoistic.

They've also adopted an idiosyncratic way of pronouncing the time itself: "The time is Four, GMT". Everyone else says "Four O'clock", or "four hundred hours" or "four AM". The Beeb are almost completely immune to complaints; they've outsourced their complaints department, and the contractor's brief is to make sure no complaints reach programme makers.

Because they have to interact with the rest of the world, and billions of lines of computer software and hundreds of thousands of protocols have been written to use UTC instead of, say, using TAI and computing UTC on a presentation basis like timestamps are handled.