I'm going to go with the assumption with that individuals and private companies are rational. Therefore, they do what's best for them. Then the question becomes why a majority of individuals and private companies pick the synchronized schedule?
I believe that should be the angle of investigation, rather than creating theories about the grand mistakes the society makes. Everybody has more or less a brain you know :) And they can choose what's best for them. The question is why does the majority of people and firms choose the synchronized schedule?
There can be many reasons. I don't claim to know the answers. We can posit some theories, then test them through reasoning.
Number one reason might be: society needs a clock so that families can sync up. Drive kids to work. Help them with their homeworks. Cook. Eat family dinner. Both mom and dad go to work at the same time, so that they can be at home at the same time. You cannot delegate your interactions with your spouse or the kids :)
Single people and childless people do have more freedom. I remember the days where I used to go to work between 10-12am. Then leave around 7pm. Many of my single and childless friends are on a similar, shifted schedule.
So there you go. You can posit many other theories: E.g. market prices may not be dynamic enough for efficient allocation. That too might have a good reason (dynamic prices incur communication costs & may create confusion). So lack of incentives, too, must be a playing a role.
Weekday-weekday synchronicity too must have good reasons. Work gets done a lot better when your colleagues are around, you know :) Remote working hasn't caught up with the quality of face to face interaction.
Etc etc. The article misses many obvious things, imo.