It’s easier for the 2pm across the world to be aligned with daytime and 2am to be aligned with nighttime. Otherwise you would have to know the exact geographic location of each place you refer to since 2pm could be morning at one place, afternoon at another and night at another

Also the world completes one full rotation every 24 hrs, with the sun making landfall on one part of the earth before the rest (E.g. sunrise in Japan occurs when it’s sun setting in the western world). Hence it’s easier and more useful to track time around the world by using taking in account the world rotating and sunlight making landfall

Noon is midday. It can't be 2pm somewhere where it isn't 2 hours past midday. You could use the 24h system with UTC everywhere, but that's already done for any systems that need synchronization.

We don't use it in day to day life, because for 99% of people, only one timezone is relevant at a time, and keeping the meaning of different times the same takes precedence.

Also useful is knowing what the average person is doing in a country you're interacting with. If I message my coworkers in Romania (arbitrary country, I have coworkers there) at their midnight, I know I won't get an answer till their morning. If it just says 15:00 or whatever on the clock and there's no timezones, I would have to put in significantly more effort into figuring out if people in Romania are sleeping now.

I can barely get my head around the fact that the seasons are flipped in the southern hemisphere compared to here in the north! Traveling would be a bit odd. It’s nice to know that I have the reference point of 12 being either in middle of the day or night no matter how far I go. If I fly 10 hours away and land when it’s dark, how would I have a clue how long it was until the sunrise?

In the late 90's early 00's there was something called Swatch Internet Time that was a 0-1,000 time scale measured in "beats" that operated under this idea but obviously it never caught on.

>For example being 2:00 pm on USA

Where in USA? It has six timezones.

The answer to your question is another question:

How many people will agree for their solar midday (i.e. sun at the highest in the sky) to be at, say 5pm. Timezones are there for people's convenience. Having to account for time zones is something relatively few people have to consciously do, even today. And if they have to, they will usually use UTC as a reference, because it's the reference standard timezones are arranged around.

Even certain countries adhering to am/pm itself just shows what the obstacle would be. You can't have a 4 post meridiem (AFTER MIDDAY) if midday is several hours away. And trying to get them to simply use a 24h clock is an uphill battle, much less accept a time that doesn't align witg their day.

TL;DR It'll be possible to unify the world's time when you, the OP, will happily agree that your sunrise is at 17:00, your midday is at 23:00 and your midnight is at 11:00. Why those times? Because someone else that isn't you decided that their time aligns with solar time, deal with it.

Because then you'd have countries changing from Monday into Tuesday in the middle of their day. It would be painfully confusing to everyone except the blessed few who get to live in the "correct" time zone. Most people live most of their lives locally. Your day is aligned with when you wake up, go to sleep, etc. and where the sun is in relation to where you are is more important.

[removed]

There is a standard called UST which every country can reference which will be the same no matter where one is in the world.

It simply isn't very convenient. Most societies have adopted a convention and cultural references that are more amenable to local time standards. (for example things like "9 to 5". etc)

As there is no requirement or law forcing countries or peoples to adopt UST, the choice is really theirs. It might suck that you don't like it but people don't really have to make things easy for you.

[removed]

[removed]