What do you mean "it worked"? What does that mean?
He halved his salary because Nintendo lost money for 3 years straight and people were calling for him to resign. This was also during the multi-year period where Nintendo was facing relentless pressure to do business on smart devices, and Iwata was the #1 opponent to doing so, and he finally relented in 2014 after it was clear that 3DS was going to struggle just to do half of the business the DS did, and Wii U failed to gain any traction in the market at all even after 3D Mario, Mario Kart & Smash were all released on it.
Iwata oversaw two complete hardware launch failures in a row starting with 3DS and ending with Wii U, and yeah he was deeply involved in what would eventually become the Switch, but let's not pretend he was this religious-like golden leader who was just this amazing person. He had his strengths & weaknesses, just like anyone else. And yeah, he was charismatic and he certainly was responsible for Nintendo navigating the choppy waters during the boring era of 2003-2005, when GameCube wasn't doing well commercially, and Nintendo was getting absolutely annihilated on the home console side by Xbox and PS2. He saw that a GameCube 2.0 without any major innovations was poised to not do well against a PS3 and Xbox successor, unless they pivoted and did something new.
He was a visionary, for sure. But he certainly should not be credited for the salary cut thing. He deserved to take a salary cut, NIntendo was *losing money* for years under him from 2011-onward until 3DS started to take off. Honestly, if your company loses money for a whole year, you should not even get a salary. Not when you're the CEO. You make money when the company is profitable, you don't make money when it isn't.