I think you're reading into something that isn't there. GP never said anything about declarative being better than imperative, merely that they are different approaches and SQL is declarative.

But even if they had, your argument that the CPU ends up running imperative code makes it better seems silly. The CPU ends up "running" machine code and a compiler has to turn the vast majority of imperative code into a different form. Does that make machine code better than assembly? better than C?

I don't think so. They are simply different levels of abstraction, each with their own pros and cons. Neither are "better" than the other. Each are "better" at some tasks and worse at others.

GP said there was a "benefit" with SQL being declarative, because when you want to abstractly request some arbitrarily structured data, it's beneficial in most cases to not have to know exactly how to find and retrieve that data. It's certainly not "better" if you need to ensure some specific bit format on the hard drive. But it's "better" if you want to succinctly express a query that is broadly reusable and understandable even to people who have no idea how the database works on the inside.