So first of all, that avatar is awesome :)
Second of all, I agree with you on the relative benefits of the Nintendo ecosystem.
Third of all, I think your thesis is wrong. The fact is a lot of people have drifted away from Nintendo or simply prefer the offerings on rival platforms. A lot of people love military shooters, open-world sandbox games, cinematic action games, sim racers, and RPGs - many of which can't be found on Nintendo hardware.
I think Nintendo makes the best games in the business, but many do not. And no amount of franchise fatigue or nostalgic yearning will convince them to invest in Nintendo.