Civil time is a coordination game, so “leave time alone and just get up later” is more complicated than you think.
Imagine how it would look if everyone kept acting the same way we do now but the clocks don’t change. Everyone would need to post summer hours!
Here’s the Sun Graph for New York City: https://timeanddate.com/sun/usa/new-york
Notice how the DST transition keeps sunrise relatively constant? That’s actually a decent feature, particularly for people like me (and people with young children) who tend to get up with the sun.
And it’s not like you’re going to get tons of daylight after work or anything. The sun will go down at 17:30 instead of 16:30, but if you have a 45 minute commute and want to get to work at 8:30, you’ll have to be out the door at 7:45, 30 minutes before the sun comes up.
And they’d need to tell you when those hours start and end. In practice it would be a random mishmash of DST transitions on a per-service basis.