I never found those arguments for keeping time zones particularly compelling. Everyone has their own schedule, trying to standardise time to sync people up is silly, you sync by talking to them and asking them what times they are available. The number on the clock doesn’t actually matter.

But DST affects us exactly because people tried to standardise on time AND then shift that meaning twice a year. If we ditched timezones, then businesses could say ok we will work from 1700 until until 0100 or whatever, based on time relative to sunrise, it it would be consistent all year round.

The thing is, regardless of timezones, you have to ask people what times they work or are available or whatever. Also consider that timezones are arbitrary and made up anyway: china physically spans the space of 3 timezones yet the entire country uses one timezone.