Rust and Go both aim to create safe, performant, modern languages suitable for use from the systems layer up, differing in some of their primary goals:

Rust is a sane C++: Zero-overhead abstractions, not afraid of language complexity.

Go is a modern C: Simplicity, stability.

They have some overlap in what they're best at, but they both take on unique and important missions that both need to be targeted, in our rapidly expanding universe of software engineering.

(edit: formatting)

At this point it’s history: Go and Rust both got started around the same time - one by Mozilla and the other by Google. They’ve both reached critical-mass over the past ~10 years - so expecting one of them to disappear is like expecting Autodesk to choose between 3ds and Maya...