Of course his teammates want to keep him around. He is a great teammate and was very productive.
However, the issue is how easily that production can be replaced at a markedly reduced price from other RBs on the team, FA and the draft.
RBs just aren't worth what they used to be and that is the reason that so few of them are ever picked in the first round anymore. This year there should be a number of reasonably priced vet options in FA and it is supposed to be a deep RB draft.
In terms of Murray himself, he looked really worn down by the last four games of the regular season. He just can't take that kind of beating with that running style. The last RB we had like him was also all downhill after his fourth season (Marion Barber) and he was actually used a lot less than Murray has been. I'm sure there are still some scars left from giving Barber that 5 year $40M contract when they could have just signed him to a RFA tender that offseason. This was just another case of Jerry getting overly attached to his players and thinking his money would buy player loyalty and future performance. Well it didn't and it won't in the future either. You pay them as little as you fairly can to make the team as strong as possible because the salary cap is a zero sum game.
We will make some attempt to re-sign him because the fans and teammates expect us to do so after the productivity he demonstrated last year. However, he is not special and we must maintain cap discipline for more important players such as a pass rushing DL.