It does make a difference: only some professions are harmed from the lack of light, and only those professions would need to change their schedules to follow the sun.
When you change the clock, it affects everybody. But people can change their own (business's) schedule without affecting anyone else.
But it is easier to accomodate to if everyone is affected, everything is connected: you may not be affected, but the school of your kids is, and the opening of daycare, the opening times of the stores, your sports facilities, etc.
If everyone changes, you can keep all the dependencies the same, otherwise you have to reconsider all dependencies.
> it is easier to accommodate to if everyone is affected
This is theoretically true about a lot of things, but we don’t try to actually do it for almost any other case. For example, it would be easier to accommodate wheelchairs if we just outlawed stairs and made it so every grade-separation must only be bridged by a incline. But we don’t do that. We build the incline, but we also continue to build stairs.
When you change the clock, it affects everybody. But people can change their own (business's) schedule without affecting anyone else.