The most convincing argument for imperial linear measure is the good size of the inch and foot, but millimetres are fine, so the loss of those friendly sizes doesn’t hurt

The hour is a comfortable size, a metric day would have a ten or hundred hour day, hours wouldn’t be anything like the eight for work, eight for sleep, and eight for shitposting

Working in seconds isn’t a good workaround

We would definitely be fucked over in any recalculation of how many metric hours we should spend working

The past changes to week lengths were particularly disliked by the religious people who believe the weeks have been running Monday to Sunday (or Sunday to Saturday) from the beginning of time

And again we have a status quo of two sevenths of a week being for recreation, if we had a ten day week three day weekends would be longer than our current, but would have seven continuous work days

Also you would need names for the additional days