I wouldn't go as far as "falsehood". Leap seconds aren't inherent to timekeeping. It's easier to do without them, and a system like that isn't wrong.
* Drift between terresterial and sidereal time,
* Drift between terresterial ground level (1G gravity mean 'surface') and orbiting satellite (eg: GPS time)
* Differing frames of time reference best suited for different tasks.
Common computer time server synced time is based on the nominal notion of "mean noontime" UTC .. or the rotation time of the earth to move from Greenwich "pointing at the sun" to again "point at the sun" (perhaps surprising to some NOT a full "360 degree" rotation as the earth has moved forward on its orbit).
Myths about time that programmers should know is a good read .. eventually drift between systems must be addressed ( GPS sats use "epoch time" (local atomic clock ticks) lapsed "per week" and GPS recievers reconcile relativistic drift using broadcast corrections ).
Any significant scientific data collection program (geophysics, astronomy) required the use of some form of "epoch time" with accurate local clocks not synced to UT | GMT | Zulu time servers.
Your apparent desire to not deal with adjustments on the order of a second during your lifetime is simply pushing the problem down the road until it's a case of reconciling hours .. or even 11 days (as has already happened in history).
> Your apparent desire to not deal with adjustments on the order of a second during your lifetime is simply pushing the problem down the road until it's a case of reconciling hours .. or even 11 days (as has already happened in history).
An hour, or fraction of an hour, is significantly easier to reconcile. Even assuming we stick with the same system for that very large number of years.
Fractions of hours require the same effort of understanding the issue that seconds do.
Where it matters (my field) we use absolute lapsed seconds in a specific framework and don't rely on sync'ing to UTC.
Fractions of hours are just a time zone. Time zone changes happen all the time. Much easier than shifting the underlying clock.
If you have a genuine interest there are some decent starting links in this thread that you might pursue.
It's actually more than a 360 degree rotation because the earth rotates in the same sense that it revolves. So the sidereal day (1 earth rotation in physics sense) is ~ 23h 56m, and the 24 hour period is over-rotation to bring the sun back into same position, and that's more than 360 degrees of rotation.
Leap seconds are inherent to timekeeping based on the sun, which all civil time is. Without them, "midday" and "midnight" become undefined.
And it's not like allowing .9 seconds of drift is objectively correct either.
A second of drift is negligible, but a minute of drift pushes the boundaries of time zones sideways by 6086 feet at the equator.
But having the average solar midnight match that very specific spot is not important.
> A second of drift is negligible, but a minute of drift pushes the boundaries of time zones sideways by 6086 feet at the equator.
Which doesn't matter when they're 60x that size wide. Especially when countries will shift an entire time zone for fun.
A minute of drift is also negligible for civil time, as long as everyone is in sync, and we can't really predict the timekeeping future beyond that first minute of drift.
You can get a legislature to change your time zone faster than the problem leap seconds purport to solve can become relevant.