The following is a bit of a rant so I apologize in advance.

I'm not a programmer, but I understand enough about systems administration to know why monotonic time is important.

But leap seconds exist for a reason - the rate of Earth's spin is not constant, so since the invention of clocks accurate enough to be able to tell that, we have had to invent a way of compensating for the variable rate of spin such that "midday" is still the middle of the day and "midnight" is still the middle of the night. Without adjustment, these concepts would slowly drift.

It makes me angry that programmers feel that they "own" the concept of time measurement enough to propose the abolition of leap seconds. The definition of unix time excluding leap seconds is really the origin of this nonsense, and it has always seemed to me that the obvious solution is computers should simply measure seconds since the epoch. Wikipedia describes this version as the "TAI-based variant" of Unix Time, and if we all used it, computers wouldn't even have to care about leap seconds, and conversion to standard time display could be done in userland, accounting for leap seconds in the process.

Civil time is more important than keeping your log files in order. Get your computers to count seconds, and leave more important human concepts like midday and midnight to the humans who are affected by them.