I don’t think the event had any bearing on the length of his career. I think as the game has evolved, the kind of role that plays to his strengths is becoming marginalized & obsolete.
Teams want LBs who can stay on the field in Nickel. They want guys who not only take on Guards but who can also run with WRs.
31 year old run-stoppers who are only useful in playing the run are not high in demand.