Again, I'm not saying Nintendo is going to experience a PS4-esque turnaround with this one console. The NX should be a big step in the right direction. Do away with the old, conservative, "fuck third parties" Nintendo, and enter the future.
If Nintendo creates a console that is the best place to play for the lowest price, it will raise eyebrows. Will there be a mass exodus from Xbox and Playstation? Probably not. But people will take notice. People will realize that Nintendo is actually going after the core audience and offering something that the competition can't quite hang with, and that's quite the statement. If the PS5 and Xbtwo drop right alongside the NX2, and Nintendo once again is offering the most attractive console for a reasonable price, who's to say people won't jump ship to Nintendo?
Of course, Sony's dominance over this gen came with quite a bit of good fortune. Xbox managed to completely destroy their brand with the botched reveal of an overpriced, underpowered console. Even now they haven't been able to bounce back. Meanwhile, Nintendo's Wii U was made irrelevant basically as soon as it launched. The opportunity was right there for Sony, and they took advantage big time.
That being said... it's not like the PS4 isn't deserving here. It's a great fucking console. It's well built, has the best console versions of a bunch of great games, and was priced perfectly. Not to mention the fantastic marketing. I look at how the reveal, marketing, launch and lifecycle of the PS4, and I see very few mistakes. Nintendo should take some notes from the market leader, it's as simple as that.