Maybe the universe is full of intelligence it's just that there's a lack of humans. That is to say, it's not humans that are intelligent it's the civilizations of bacteria and viruses that live in and on humans that are intelligent.  Apex creatures are very sensitive and fragile, mitochondria and their allies only just barely managed to cobble humans together. There's bacteria sitting around right now on Europa saying "damn, if only we had humans we could build rockets and get out of this hellhole." Then their boss comes in and says "we pay you to make ATP not daydream about Elon Musk, now get back to work!"