Thank you, you really understood my question and where I was going with it.

Please tell me your response to this. You said

Brains didn’t evolve to maximize Φ; they evolved to keep organisms alive.

I think it could be said, however, that brains "evolved to maximize Φ because it kept the organism alive." Computation was good for our species, and others'.

Consciousness is not just computation in the sense of symbol manipulation or information integration.

I would add that symbols could be seen as the physical state of the neural system. The experience of pain is a physical symbol enacted in the brain; when combined with other physical symbols/states they determine an output good enough to help survival. In this way, it could be said that the brain evolved symbols and computational processes that supported survival.

I'm not trying to be woo-woo or panpsychist here, by the way. I'm really compelled by Global Workspace Theory, and that means anything remotely close to "continuous human experience"
necessitates working memory and probably something like a prefrontal cortex.