There are inherent risks when a ball club lets a fan favorite go. Pujols left for the money. While he was popular and a great player, the fans didn't get too bent out of shape. Hell, I remember when Simmonds got traded and people in my circle didn't go back to a game for years.
There's a basket full of players that fit that mold and Yadi is in said basket. From a baseball perspective you are 100% correct. He's older, not as tough defensively and injury prone. From the human perspective though, there will be hell to pay among his supporters if they trade him and get nothing much in return.