The popular opinion about time zones is that they are hard, complicated and there are just too many of them. There are hundreds of time zones (depending on how you count them), yeah I know there really is only around 24 time zones (some timezones are 30 or 45 minutes apart). But for every time zone, there is a dozen of names, some are descriptive like America/New York tells obviously the time in New York, but for the same time zone, there are other not so descriptive names.
UTC means Coordinated Universal Time, it was created as a standard to all time zones. It tells the offset from Greenwich like UTC-4, that would be New York, and is quite straightforward. It definitely makes time zones a bit easier, but there is one problem. People don't want to use it, especially in the US (Damn those Patriots, this reminds me of the same problem we have with the SI-system)
I don't have a clear answer for this. Most likely it has something to do with the fact that people in the US are used to their time zones and in Europe for their time zones. As Internet grew bigger and bigger it was the first time's people really had to start using time zones in their everyday lives. Because they had already used their "descriptive" names for timezones they just wanted to keep using them from habit. If you have your whole life used ET (Eastern Time Zone) why would you suddenly change it and use UTC instead?
Because people are used to their own time zones creating a new standard for time zones doesn't help. Something we can do is create tools like the time zone bot and this website Countle to make it easier to see when an event/time happens. Time zones will always be hard and we need them. Some people suggested that we just create one time and people have to get used to it that 7 PM is noon etc. But that just isn't going to work. It would require changing even stronger habit, telling the time. Creating tools helps a lot of people and solves the hard part, memorizing different time zones. The time zone bot is doing this work in the Reddit and Countle allows anyone to create time with time zone as a countdown.