The example you give to prove plausibility is also a counterexample to the argument you make immediately afterwards. We know that less-intelligent or even non-intelligent things can produce greater intelligence because humans evolved, and evolution is not intelligent.
It's more a matter of whether we have enough time to drudge something reasonable out of the problem space. If we were smarter we could search it faster.
Evolution is an optimization process. It might not be "intelligent" depending on your definition, but it's good enough for this. Of course, that just means that a rather powerful optimization process occurred just by chance. The real problem is, as you said, it's extremely slow. We could probably search it faster, but that doesn't mean that we can search it fast.
This thread is for asking any questions that might seem obvious, tangential, silly or what-have-you. Don't be shy, everyone has holes in their knowledge, though the fewer and the smaller we can make them, the better.
Please be respectful of other people's admitting ignorance and don't mock them for it, as they're doing a noble thing.
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