This is the big problem with the idea that consciousness is just complexity, and that sufficiently complex systems might become conscious. Stars, storms, gas giant planets, nebulae, etc. The problem is these things are complex yes, but except at a very macroscopic level they have no mechanism to maintain a consistent state, or to control and reliably change that state. They're just heaving masses of particles. Computers and the brain are incredibly ordered systems, and are incredibly fragile to even the tiniest disruption of that order.