The scientist even explained how when sleeping, we don't: Reproduce, gather food, innovate, socialize, work, AND we are VULNERABLE TO PREDATORS. It's basically biology's biggest blunder, and yet every single species on earth sleeps (At least big enough creatures, I think cells don't need to sleep?).
The idea of evolution means if a living organism this big could live without sleep, then it would thrive!
That just means sleep is extremely important if it still exists.