Well, he is making an analogy that real internal experience cannot be confirmed externally, however convincing the performance, but this is the only way we know about the internal experience of all things, including ones we typically assign "real" consciousness to (humans, dogs) and ones we don't (amoeba, zygotes, LLMs).
To be clear I'm not for a moment suggesting current AIs are remotely comparable to animals.
Unfortunately, this sort of thing happens all the time, you just happened to notice this one. It's not only Musk-related posts, either. Negative submissions about Altman also get flagged and disappeared. The mods don't seem very interested in countering this behavior. Often it's weakly supported by claiming the discussion is low quality. (Which is often true, but not imho a good enough reason to suppress the topic rather than enforcing comment guidelines.)
He is also not wrong about whether current AIs experience feelings. I suggest you learn more about the neuroscience of feelings.