A small syntactic sugar you can trivially implement yourself makes Go a non-starter?
Go doesn't include assert in the language because you're supposed to do better than assert. Assert easily allows lazy programmers to let their programs freely crash without properly handling error conditions. Go prevents you from compiling with unused variables, and that combined with the Go documentation goes a long way towards teaching new Go programmers how they're expected to work.
And neither Go nor Rust could possibly be good fits for SQLite. A Go hello world is bigger than all of SQLite while an idiomatic Rust one is on par, and neither's nearly as portable as the current C implementation, one that is both programatically and battle-tested like pretty much nothing else in the world.