A container runs the utility in an isolated environment without having to alter your base system's packages, dependencies, etc. Assuming the bork that necessitates a reboot is not a kernel or hardware issue, this would mean that if you get hit with that issue again in a container, what dies is the container itself, rather than your system as a whole. So you're isolating 1.- package management 2.- network config and (potentially) 3.- "blast radius".

(That said, this is the first time I've ever heard that Proton would bork the networking to the point of requiring a whole system reboot.)