True but so do most computers. Computers have a database of timezones and time offsets around the world. Depending on the UTC date and time, and your current timezone it will look up what offset to apply to show the local time. The database is very gnarly since rules change over time, e.g. maybe in the 70s some countries had longer DST to counteract oil shortages.
I feel you’re conflating TimeZones with ever-changing Daylight Savings time rules.
True but so do most computers. Computers have a database of timezones and time offsets around the world. Depending on the UTC date and time, and your current timezone it will look up what offset to apply to show the local time. The database is very gnarly since rules change over time, e.g. maybe in the 70s some countries had longer DST to counteract oil shortages.
You don’t have to go back to the 70s for changes. Kazakhstan has changed from two time zones to one just about a month ago.
And there was much rejoicing (not)