It's cool but it only works if you have a rust compiler that can actual compile this (1.55.0) and no one does. That means you have to install a compiler from outside of your system repositories 100% of the time. Is suggesting everyone,

curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh

... really such a great idea? Even ignoring the curl | sh it's going to bork many systems now having two rusts. Rust projects you're supposed to compile are not ready for use by anyone but other bleeding edge Rust devs.