Ok so there are 24 time zones. Before that every town had their own time based on the sun. We basically went from infinity time zones down to 24. This is in fact simpler.
(There are some half hour time zones too, (India, Newfoundland) so at least 26.)
There are a few time zones that are 45 minutes off, like Nepal Standard Time which is UTC+5:45, some places in Western Australia and South Australia use UTC+08:45 and the Chatham Islands are at UTC+12:45 or UTC+13:45 in summer.
DST means you also have things like CST vs CET and given some places start DST earlier or later than others and some ignore it all together, we probably have at least 50 time zones.
Always fun trying to schedule international regular meetings when suddenly there’s a week when half the people’s times changed and the other half’s times haven’t yet, so you try to figure out which time would exclude the fewest essential people.