Servo was an experimental ground for Mozilla in some ways (like testing out a new CSS engine and porting it back to Gecko if it works). So it's quite normal for people to be unaware of it, it was not meant for the public.
But later on it was abandoned by Mozilla and stuck in a limbo, until it got picked up by the Linux Foundation. Now it's a standalone project and I wish them well. We really need a new FOSS web engine.
It's always the "rarely" that gets you. A program that doesn't crash is awesome, a program that crashes consistently is easy to debug (and most likely would be caught during development anyway), but a program that crashes only once a week? Wooo boy.
People vastly underestimate the value Rust brings by ensuring the same class of bugs will never happen.