The difference is that as soon as you know what time it is in Melbourne, you know if you can call Uncle Steve. Regardless, you have to know where the sun is, be

The difference is that as soon as you know what time it is in Melbourne, you know if you can call Uncle Steve. Regardless, you have to know where the sun is, because that determines whether or not Uncle Steve is awake (most likely). But it’s much easier to find his timezone offset and figure that out than figure out if the sun is up there (which incidentally, timezones actually allow you to do). It’s much easier if noon is noon around most of the world (obviously it gets more meaningless the further north and south you get), as opposed to always having the same time and having to figure out where the sun is. This is why one world timezone is a terrible idea. It makes some calculations simpler, but it otherwise royally fucks with how humans work, and humans are much more concerned with where the sun is.