Problem you are trying to solve

I run rustup update and other commands to update the software on my PC every day. I know my installation of rustup is managed by my package manager and don't need to be reminded that it can't update itself every time I want to update my Rust installation.

Solution you'd like

A config option to suppress the message would work for me.

Notes

As someone who prefers to use software packaged by my distro, a big reason this is grating to me is because it reminds me of software that intentionally degrades the user experience when packaged by people other than its author.