If you look at the new television deal you can't fault Kawhi for asking this kind of money. Salaries are going to go up so why not ask for a contract that in a few years will be considered less than max? From my understanding the cap is a soft cap that changes based on the success and health of the league.
A few of you mentioned he doesnt put up consistent numbers but you gotta remember the Spurs don't run plays for him. Pop said that himself. They have not really made him a focal point in the offence. They have TP and Duncan who they'll continue to ride as long as they're productive. Kawhi still puts up decent numbers just playing off the flow of the game. They turned him loose in the Finals because Timmy and Tony were not able to get over the hump by themselves and you saw the results. He took over and changed the entire tone of that series. Miami did not have an answer for him.
He may not be worth max in the Spurs system because Pop seems to be able to plug players in that know their role and get the best out of them. However with Manu, TP and Timmy getting older there will be an opportunity for someone. If "Kawhi is the future face of the franchise" as Pop has stated that should be enough of a co-sign in his abilities.
On another team where he's a focal point in the offence surrounded by players that compliment him he's worth the max. 23 years old, mentored by championship pedigree, 2 Finals, 1Finals MVP with a ring, a great all around game - then read up about his work ethic and of course he can get that max. As I said probably won't be max for long. He wants to be great and he's been surrounded by greatness the whole time...Pop, Duncan, TP, Manu... showing him how to be a professional and the habits required to reach that level.
People said Harden wasn't worth the money he was asking from OKC. Well, defence aside I don't think there's too many people who would argue he's not worth a max deal. Difference is Harden got turned loose and no longer had to differ. He was told "You are our dude, do your thing."
If there is one worry I have about him its more on a health tip. All the talent in the world doesnt mean much if you're not on the court and he's had a history of on and off injuries. He's never played more than 66 games. That's what you're rolling the dice on in my eyes not in his on court ability.