If you are going to have standard/daylight time it is a lot easier to just change the clocks since clocks are designed to be easy to change.
For a while this was not true. When digital electronics became cheap and common, designers started putting clocks in everything and so a DST change might involve going through your house having to change dozens of clocks.
Before this, we'd typically only have a couple wall clocks in a house, an alarm clock in each bedroom, and our watches, most of which we had to regularly set anyway to keep them on time so DST wasn't much of a hassle.
Now we still do have clocks everywhere--I think I counted something like 20 clocks in my house recently--but now most of them are self-setting. I've only got 3 that I actually have to manually change for DST.
Hahaha
There have been immeasurable amounts of engineering put into this, and it still doesn't reliably work.
That apart, there are so many countries in the world with vary different day light timings based on season and very few of them have daylight savings time.
Although historically, if I'm not mistaken, it tends to be in the other order. Government services tend to sync up with what everyone else is doing (my understanding is that the 8 hour day originated in the private union movement and only came to government work later).
Example: 8am-3pm during winters. 9am to 4pm during summers etc?