Saying they had a shit ton of space as a result of that deal is a little misleading. I recently commented about something similar so I'll just repost the relevant parts.

The Warriors extended Curry 3 years into his rookie deal where he was coming off a season where he only played 26 games. Sure he could have just played out the last year of his rookie deal and hit FA, but he hedged his bets and took a 4/44 extension with some uncertainty about his ankles. The Warriors took a gamble on his health too. That contract wouldn't look great if Curry struggled to stay on the floor and plenty of people had doubts about that.

But even if he does decline the extension and play out 2013-14 I believe the max he could have got was just shy of 4/60. So, while a 15 mil difference is pretty large, it's less than 4 mil a year as far as payroll goes. The main thing that helped them was that he played out the 4th year under his rookie deal before the extension kicked in, so the contract looks better because it was signed a year before it kicked in. I know people like to point out the Curry contract as a big reason for GS's success and, even though it does help out a lot, it's not like it was a franchise defining contract.