Will the Switch 2 have some secret sauce? If so, what?

[Slownenberg]

Wman1996 said:

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Switch 2 needs no secret ingredient, at least not out of the box.
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Switch's hybrid nature is enough to make it unique in the field. Nintendo just needs better specs and games people want to play and you're looking at 100 million at least, possibly 115 million or more.

exactly. The secret ingredient is do the same thing with current technology and improve everything a little bit in whatever ways they've come up with from the experience of making the first Switch.

The hardware should be an iterative update. The software, specifically their whole online setup, is where they can innovate and by innovate I just mean catch up to where the Xbox was 20 years ago lol.