No.

Just because everyone is working off the same clock, doesn't mean everyone is going through their "day" at the same time. That's actually part of the point. It would force people to stop using the traditional times for things. Traditional times insist people use a "close but not quite right" clock, being off their natural cycle by and hour or so. Prior to the standard 24 timezones there were hundreds of timezones, because diffrent towns started their days at different times. Still they all insisted on using the same clock number for that time. It worked great for them but was impossible for everyone else to keep track of. If instead, everyone agreed to use the same global "timezone". It would free up everyone to start and end their day when it made sense for them; At the same time, make it easy when coordinating things over distances.

Just look at your pay-stub to see what it means for you. Here is what it looks like on mine.

So far this year I have paid $215.92 into Medicare, and $825.59 for my health insurance, totaling $1041.51.

Medicare already covers our demographic with the highest medical expenses by a long shot, our elderly. For easy napkin math though, lets assume for Medicare to cover everyone it would cost twice as much as it does now. It won't, but it's an easy assumption.

My Medicare tax doubles to $431.84. I don't have to pay for any health insurance, saving $825.59. The total out of my pay would just be the $431.84.

$1041.51 - $431.84 = $609.67

I save would $609.67 switching to Medicare for all, if it costs twice what Medicare currently does. Go look at you pay-stub. See what it will mean to you. Double your Medicare tax, eliminate your health insurance. Do you save money?