you'll grow more as a developer from rust. Rust will force you to think about things like memory management, safety etc. additionally, it has a rich set of abstractions. rust also has better interop with c and c++. In the long run, you're better off learning rust. You'll encounter a brutal learning curve but once you know it, you'll find yourself able to do very powerful things with ease. especially once you internalize the borrow checker.

Go is a great language for the short term but I don't feel like it brings Anything unique or interesting to the profession. its only real advantage is that its quick to learn but there isn't much substance. Its a great language if you're the type of person who doesn't mind copying large reams of code to change a few lines for a new purpose.