Sleep is a very technical thing, it's a 'Brain maintenance time'. It's not about saving energy or anything that could/should be bypassed (otherwise we'd be tired awake at night, useful for defending against predators in the wilderness -- nature accepts a great cost for this shutdown). I find my memory improved significantly once I started being more careful with my sleep, for instance. I wish I had come into contact with this instead of the bragging 'I barely need any sleep!' culture.