Why is he needed more than Savard on this particular edition of the team? This is the question I'm asking you. Savard is a vet, who has won the cup, and doesn't mind mentoring the young kids coming up on a losing team.
If Mike Matheson is absolutely needed for the next two years, what does this team accomplish overall that it doesn't without him on the team? Do they make the playoffs? Do they win the cup? You talk as if the team is really good, Matheson is a core part of why, and trading him will throw off the entire balance of our offense. This isn't the case.
If he's here mainly for mentoring, we can get a veteran defensive D on the UFA market for 1/2, 3/4 of the price. Nobody is suggesting to throw Lane Hutson/Mailloux/Reinbacher/etc to the wolves and take up his ice time/role, it would just be spread around to various other members.
Even if I liked Matheson, he would be classified as a nice piece to have currently. Given his age and the fact that he's under contract for the next two years only, he should absolutely be on the table for any sort of trade that improves this team's future prospects.