The other use for timezones besides local midnight is the offset between geographical areas. UTC+2 or UTC+4. if I start work at 6 UTC and my buddy at 10 UTC, I know for scheduling purposes we are 4 hours shifted from each other. Whether you have to do math or not depends, but it is still a “timezone” by a different name. The only way to completely get rid of timezones is to ignore local time altogether.
Except that in practice you’re still adding people’s personal schedules on top of the time zones, so just accounting for their personal schedules in UTC makes things easier.
The other use for timezones besides local midnight is the offset between geographical areas. UTC+2 or UTC+4. if I start work at 6 UTC and my buddy at 10 UTC, I know for scheduling purposes we are 4 hours shifted from each other. Whether you have to do math or not depends, but it is still a “timezone” by a different name. The only way to completely get rid of timezones is to ignore local time altogether.
Except that in practice you’re still adding people’s personal schedules on top of the time zones, so just accounting for their personal schedules in UTC makes things easier.