What about the simple fact that biology is a dynamic substrate running actively and always on, whereas silicon is passive substrate that can be indefinitely off and can never self start? Sure you can imagine nanotechnology that has similar flexibility, but when you do, you’ll find that carbon is particularly better than silicon when it comes to possible configurations.

It’s not a reach to argue consciousness is a property of the dynamic substrate since clamping specific dynamics does in fact seem to ablate consciousness. Most famously with death.

On the flip side, a hibernating organism, while having very slow dynamics, has shown to still be aware of certain seasonal signals, and thus is able to self start its next conscious period.

None of this is mystical or magical. Nothing but the physics of active matter. Which current silicon is completely not.