We can't not consider current timekeeping. There is exactly 0 chance we can get everybody to change in the same instant and even if they did history is still there. Education, and thus civilisation's shared consciousness, will include the old timekeeping until the renaissance, industrial revolution, the inventions of computers and space travel and the near-ELE cataclysm of the final death knell of religion are all historical footnotes. Computers will need to understand the old timekeeping forever. We won't reduce the amount of bullshit humans deal with, we will have increased it. And with all that, the earth's orbit still won't be 1000 days.
And all for what? So I can count the hours in a day without getting my feet cold? Woo!
Well we use to use cubits and chains for measuring everything too. Science is slowly moving to si, we should probably all start cobaidering a proper system for time that works around metric.
I don't like the idea of explaining to my children that we use this system, because it's the way it has always been done. That's a horrible idea .
I look forward to teaching my child that we use this system and using its peculiarities to spawn discussions on number theory, astronomy, history, even art.
Well we could just convert a second, day, month, year into metric.
(Thanks for the answer btw, was curious :-) )