In practice, parents will push their kinds into learning while asleep. Millions of Chinese and Indian students will cram while sleeping. Sheryl Sandberg will write a book about how women need to sleep learn with more vigor. Corporations will require workers to do overnight sleep-learning in preparation for tomorrow's meetings. People who don't utilize their sleep time effectively will be outcompeted by those who want to succeed at all costs. Human "rest" will be relegated to the books of history.
Is that really the sort of world you want to live in?