Because of this man:
Johto and Kanto were able to fit inside Gold and Silver.
Melee was released on time for the GameCube.
And a lot of people still have their jobs when the 3DS and Wii U were off to a poor start and Nintendo was losing a lot of money, because he took a massive paycut in his own salary.
He was a leader in every sense of the word.

He designed the Switch didn't he, well he went out with a winner!

Dear Mr. Iwata, it's been 2 years isn't it. You must have missed a lot of event. Let me tell you about a few things that you missed. In the last 2 years:

-Pokemon GO was released and it's a global success. Pokemon craze is all over the world again. And it end up with the massive 3ds shortage during the last holiday because everyone is buying it for the latest pokemon games, Sun/Moon.
-Your last baby, the Nintendo Switch has been released. It came out with the critically acclaimed The legend of Zelda Breath of the Wild, probably a GOTY winner if not for another great game coming soon later this holiday, Super Mario Odyssey. It's been a great time, but classic Nintendo never learn. Shortages are everywhere. People are waiting just for the chance to win a Switch,

It's been a great time to be a gamer thanks to you, Mr. Iwata. It's so sad that you died at the wrong time. It's so sad you never have a chance to see your baby now. Wish you Rest In Peace

We don't know how much input he had though. I highly doubt what we're playing today was finalized 100% two years ago. 

Has it only been that long? It feels like a long time ago. I remembered when it happened. I was so shocked and in disbelief. How can such a thing happen? I don't think anyone saw it coming not even Nintendo.

Oh well the world goes on but Iwata's legend will endure.

I remember reading a tribute to him from the creator of Earthbound, and literally started crying. Was one of the most heartfelt things I've ever read. I remember it didn't hit me until I read it. Always seemed like a quirky dude in the Nintendo Directs, but seeing a friend comment on it really humanized him for me.

Here it is: http://nintendoeverything.com/earthbound-creator-shigesato-itoi-on-iwatas-passing/

Anyways, thanks Iwata-san, your legacy won't be forgotten.

2 years later and it still hurts. I still miss you Iwata ;_;

Man. I remember that day. I'm actually nostalgic for it. Not for his death, but the kind of life I lived back then x.x

Its been two years?!