There are 100 decimal seconds in a decimal minute, 100 minutes in a decimal hour, and 10 hours in a decimal day. Each second is slightly shorter than a SI second.
Unfortunately, there is no easy way to decimalise time for human use. If you make it useful for humans, it doesn't sync well to a day. If you make it sync to a day, the resulting units are awkward for the human mind.
Amusingly, for computers, time is decimalised! UTC is a fully metric time. It's just simpler to constantly remap to and from UTC to a user's time, than to train the user to use UTC.
However, humans can get used to longer/shorter seconds, minutes and hours. Arguing the opposite is like saying the meter would never work because it doesn't have a human body relation like feet. The problem is the sheer amount of documents, equipment and SI using the 24/60/60 system, and the indivisibility of 365.24.
The divisibility of 60 is useful, too. It has 1, 2, 3, 4, 5, and 6 (plus any combination of the above) as factors making dividing time a relatively simple operation.
Uh, hell no. There should be ten months a year, ten days in a month, and ten hours in a day, ten minutes in an hour... and we should all use artificial lighting with scheduled blackout blinds to make the daylight hours line up. Putting everyone in the world on the one true timezone.
Today is Jan 1, 2312 . Tomorrow is Jan 1, 2313. My birthday is Jan 1 every 365 years for 1,095 years starting on year 2493, then Jan 1 366 years later. After that, repeat the thing.
I like the spirit, but it needs tweaking. Sept, Oct, Nov, and Dec need to go back to being 7, 8, 9, & 10, respectively. Also, make the leap day at the end of the final month to keep all the weeks starting on the same day of the week.
It seems the leap day should just be next to the New Year's Day, not randomly in the middle of the year. Most people then get an extra long weekend (almost) every 4 years.
If we're doing that, we should fix the month names. We start off really strong with January, named after Janus, Roman god of doorways, transitions and new beginnings. Banger name for a month honestly. Things remain pretty solid up until June, then we completely drop the ball in the second half of the year. Honoring two egotistical tyrants, then we just give up and number the rest of the months, and incorrectly at that.
No but everyone's life will be easier. Fortunately, most space agency empoloyees are scientists who embrace the metric system because it is less error-prone and does away with arbitrary conversion like in3 / floz. Space civilians will hopefully follow suit.
Metric also has a different unit name for force (N) and mass (kg) as opposed to the ambiguous pound – which works well enough on Earth but not on bodies with different gravity.