Nintendo is gambling that shiny new hardware coupled with their biggest Zelda game in history will carry the Switch at launch, and guess what, they are right. Switch will be sold out immediately at launch. Zelda is going to carry Switch until the release of MK8 Deluxe and ARMS, which will inject some needed energy to maintain any momentum. Then we have Splatoon in summer, and Mario Odysey, Xenoblade 2, Fire Emblem Warriors, and Skyrim to carry Switches first Christmas. By launching in March, this will allow Nintendo the opportunity to gauge the popularity of Switch, and make adjustments if needed. I wouldn't be at all surprised to see Smash Bros U get a port to Switch, announced at E3. This is a strong year one from Nintendo. How much weight do these games carry in 2017? I don't know, going to be interesting to see Switch either really take off or fall flat on its face.
Honestly, I agree. Switch is going to be THE Nintendo system. If Nintendo truly lets the 3DS die and fires on all cylinders on Switch, it will be a very desireable console even for people who already own a PS4. It will really depend on how they go about it. If they also keep on making new IPs like Splatoon and ARMs, that could bring in a lot of people who were simply tired of Mario and Zelda.
There's a lot of ways they can make this thing very successful, despite the current negativity.