I think the things Rust has had to sacrifice on the altar of zero-cost abstraction (mostly, garbage collection) mean that it will always be harder to use than Go.

The orthogonal fact that it's a much richer language also means that it will always be harder to learn, so Go has advantage in the niche of beginners' language, or second language, particularly for people who mainly work in an untyped language, and so don't already have type system instincts to lean on.