It's not always as simple as that. Besides it's far simpler from a personal perspective for me to set my clocks forward/back twice a year that move my entire daily schedule forward and back twice a year.
It's maybe a selfish reason, just to get a little more daylight in the evening, but I'm not the only person who thinks this way.
But... isn't that just semantics? I mean, you ARE moving your schedule twice a year. At least according to your brain. That a clock says is secondary I'd think.
No, what the clock says is primary, because it means that's what the people around me are doing also.
If it's only me moving my schedule, then I'm getting up an hour earlier, eating breakfast an hour earlier, starting work an hour earlier, getting hungry for lunch an hour earlier, finishing work an hour earlier, going to sleep an hour earlier etc.
It puts me out of sync with everyone else around me. Yes I'd get used to it eventually as would people around me and then I'd switch back half a year later.
If however the clock moves, then everyone around me is moving their schedule too, and we are in sync.
It's maybe a selfish reason, just to get a little more daylight in the evening, but I'm not the only person who thinks this way.