I hit almost this exact situation at my last gig. It came down to one of two things: was I okay with complete job security while being completely bored and apathetic all day, or would I take a bit of a leap of faith if it meant getting out of a rut? I chose the latter and it worked out. Maybe if I was a higher-up I would have tried to fix things, but it wasn't really my responsibility at the time. I'm not completely absolved; I could have tried harder to institute things like PRs and linters, but my give-a-fuck was far below the threshold it would have taken for me to really take action.