No, university professor tenure is not valuable or worth maintaining, because it makes professors willing to express and impose very strange viewpoints. If I knew I could not be fired, I would try as hard in my job. Professors knowing they have tenure know that they can adopt weird points of view and brainwash students into weird points of view.
Having taught college and having worked in other areas of education and industry, it seems as if the tenure idea for professors is an outdated one. It was begun so that free speech could exist in the academy. However, now it is a hurdle that most be crossed through publication. And once crossed, it provides lifetime job security even when a poor job of teaching is done.