1) Daylight saving time has absolutely nothing to do with this, and in any case a lot of people, me included, are of the opinion that DST is a Bad Thing and should be abolished.
2) If you want to let everybody in the world know when something specific happens (e.g. the launch of the first manned Mars mission), then you specify the time in UTC. But.. that's what we do already. Or at least those with some sense. There's still no need to force Joe Nobody to get to work at 14:00 (assuming a single world time zone) when the sun rises.. there's no advantage for people elsewhere in the world. You yourself argued that "most people aren't scheduling phone calls or meetings with unfamiliar locations". So, what's the advantage here?
3) I happen to use a calendar which is coordinated with others - it happens automatically, when they schedule something. And it has zero problem with the time - it's not just date. There's zero to gain by using UTC as localtime everywhere. That does nothing for the calendar.
4) Cultural differences in work hours: They absolutely exist. So what would having everybody use UTC help with? You still have to know those differences. It's even worse then, because if my stepson tells me "I have to work to 10AM" then I know it's late, for him. I know it instantly. If he had said "..have to work to 13 UTC" then I'm lost. I don't immediately see that he's actually working very late. I'll have to think "let's see.. he's in Tokyo, so that would be, hmm, this many hours difference from here.. is there an issue here? Oh wait, "you're working really late, will you be you okay?"
5) And that statement ".. most people aren't scheduling phone calls or meetings with unfamiliar locations". That's false. We're not in the 19th or even the 20th century anymore. The internet is a thing, and tons of people are in daily contact with people from all over the world. Just a moment ago I got a message from an airbnb guest, for example.
4) Argh, I meant 10pm or it doesn't make sense - I shouldn't try to use English time-units, I should stick to the 24-hour system I know. I always mess up that.
2) If you want to let everybody in the world know when something specific happens (e.g. the launch of the first manned Mars mission), then you specify the time in UTC. But.. that's what we do already. Or at least those with some sense. There's still no need to force Joe Nobody to get to work at 14:00 (assuming a single world time zone) when the sun rises.. there's no advantage for people elsewhere in the world. You yourself argued that "most people aren't scheduling phone calls or meetings with unfamiliar locations". So, what's the advantage here?
3) I happen to use a calendar which is coordinated with others - it happens automatically, when they schedule something. And it has zero problem with the time - it's not just date. There's zero to gain by using UTC as localtime everywhere. That does nothing for the calendar.
4) Cultural differences in work hours: They absolutely exist. So what would having everybody use UTC help with? You still have to know those differences. It's even worse then, because if my stepson tells me "I have to work to 10AM" then I know it's late, for him. I know it instantly. If he had said "..have to work to 13 UTC" then I'm lost. I don't immediately see that he's actually working very late. I'll have to think "let's see.. he's in Tokyo, so that would be, hmm, this many hours difference from here.. is there an issue here? Oh wait, "you're working really late, will you be you okay?"
5) And that statement ".. most people aren't scheduling phone calls or meetings with unfamiliar locations". That's false. We're not in the 19th or even the 20th century anymore. The internet is a thing, and tons of people are in daily contact with people from all over the world. Just a moment ago I got a message from an airbnb guest, for example.