I believe C will never die, but I'd still learn Rust or something as a backup for more modern "kinda low level" projects in order to not forever work on legacy stuff.

Nobody really uses it for application programming anymore but in areas like operating systems and firmware it’s still the lingua franca.

I've been an embedded guy my whole career and it's all been nearly exclusively in C. I'm a Rust evangelist though so I push that whenever I can.