I was told this story by teachers in an attempt to keep us off of drugs. However, I think it fits this situation nicely too.
Try to imagine the coolest guy you went to school with throughout K-12. You know, the guy who had a million friends, was captain of every sports team, had all the girls he wanted, and even got good grades too, without being a bully or unlikable in any dimension besides envy. Every guy in the school wants to be him. Then, everyone goes off to college and few keep in touch. Time passes and you eventually see him on the side of the road as an unshaven crack addict whose once awesome life completely fell apart. He has no money, no girlfriend, and no one wants to be like him anymore. You have no idea what happened to him, but he is certainly not the giant you once looked up to anymore. What's even more pathetic is that he has no idea that anything changed and still acts like he thinks he's hot shit whereas he now he only smells like it.
This is the story of Nintendo. They had every advantage, cornered the market early, branded the video game world's most beloved and iconic characters, were practically the sole force in the industry for years, and then, something happened, and they were reduced to what you see before you today.