So sorry of the loss of your sweet Max. Keep the wonderful memories of him close to your heart and he will always be with you. He sounded like the perfect pup. You gave him the best life and he knew it.
The last two males I lost were 7 and 8 yrs. old. Usually they are 10-12 yrs. (large dogs). I guess it's just "the luck of the draw". We never have them long enough, no matter how old.
You have my deepest sympathy.