I don't know, you'd still need to coordinate based on local time, let's say I want to set up a meeting with colleagues from different time zones at 10. I have no idea what time of day that is for them, are they sleeping, having lunch, etc.
With time zones, I can look up the time offset, with universal time I'd have to check their location and what time of day it is for them, which could be confusing, how do you map it exactly, bed time, lunch time, one hour before lunch time, two hours after bed time?
The other problem is that I don't think habits would be easy to change. Right now people in some european countries want to stay permanently on summer time to have more daylight after work.
We could just as easily stay on winter time and have everyone go to work earlier, shops could open at 7 instead of 8, etc. But for some reason this isn't considered, so I assume it's easier to enact all year DST than to change working hours.
Another thing is that having the change of calendar date in the middle of your waking hours is rather annoying and potentially confusing, and everybody in the world not living near wherever the meridian ends up will be subjected to that. (Because in that case a single calendar date can refer either to solar date A in the afternoon/evening, or solar date B in the morning).
Like should public holidays e.g. start and end right in the middle of the solar day because that's when midnight UTC happens locally? Do you reintroduce time zones by the back door by defining a local start/end time for day-based events to align them back to the solar day?
The other problem is that I don't think habits would be easy to change. Right now people in some european countries want to stay permanently on summer time to have more daylight after work. We could just as easily stay on winter time and have everyone go to work earlier, shops could open at 7 instead of 8, etc. But for some reason this isn't considered, so I assume it's easier to enact all year DST than to change working hours.