I definitely agree with this and had the same experience. I sort of stumbled on this accidentally while working on personal projects late after work, sleeping on ideas, and then resuming the mornings before work only to realize I was more way efficient and had better clarity during the mornings.
Eventually I just ended up mostly re-allocating my evenings to recreation and relaxation which I felt had a positive impact on my life balance.
This is excellent advice. In the past, I've often tried to do my personal projects after a long 9 hour work day, and it was just so difficult to pull myself together to put the effort, even into projects that I loved and had a passion for. The few times I have tried working in the morning however, have been amazing. I'm full of energy, and able to put my best into the project. I 100% need to remember this advice always.