The algorithm is doing pretty much the same thing that a brain is doing, except it's a smaller and slower brain, so it's not that smart, and we hardwired some parts to fill the gaps.
this is just an idle extrapolation that is not based on any fact.
if the brain was a computer in your sense of the word it would have been decoded by now.
we don't need to get metaphysical (if that is your worry) to accept that we don't know yet exactly what is going on in the brain.
Of course not. Existence of an equivalent computer program doesn't imply that it's easy to infer it.
> we don't know yet exactly what is going on in the brain
That's why it's an unreliable way to judge the distance to human level intelligence.
It’s clear that computation is one of the brain’s primary functions. Does that make it a computer (albeit one that works very differently from a macbook)? I’d say yes, but it’s essentially a question of semantics.