> I'm asking on what basis you claim it to be categorically impossible.

Because the neural correlates of consciousness wouldn't exist in their brain. I've even looked into what happens if someone, blind from birth, takes LSD. There aren't any large scale studies as it's very difficult to get approval for them, but the short answer appears to be that they don't see things: https://www.livescience.com/62343-psychedelics-lsd-effects-b...

> How is a multimodal LLM taking in RGB data fundamentally different than what your eyes are doing?

The multimodal LLM is a program run as a process on a computer, which isn't aware of what it's running: it's just blindly, repeatedly, executing whatever instruction is at its program counter. The LLM itself isn't doing anything. It's just sitting somewhere in memory being executed by the computer. Brains, on the other hand, don't run programs. Each part of the brain has a special purpose, and somewhere in it there are neurons which correlate with what is being experienced whenever something is looked at.