Is it worth learning Rust mainly because of Cargo?

So I come from a C++ background, tbh I have not learned much of STL and jumped straight to Unreal's C++. But now I wanna make some apps outside of Unreal and the thought of using C++ there makes me sick. I hate CMake and the thought of manually having to adjust a library I download just to include it properly even worse if that library uses a different build system. Then I saw Rust has its standardized package manager and thought maybe I should give it a try.

This would be the main reason as I never really used parallel programming (but who knows I might start).

Also is there some good and lightweight GUI libraries for Rust that don't force a native look?

Sorry if this has been asked before