I see this somewhat differently. I see the Switch not so much as a portable in the traditional sense.
To me some of the most compelling and innovative console features of the last few generations are off-TV play, remote play, and cross-save. But none of the implementations of those on previous systems were great experiences. Off-TV play worked well on the Wii U but you couldn't take it out of range of the base system. Remote play on the Vita was a great idea but in practice it has lag issues and isn't ideal for all types of games because of missing buttons. And cross-save never worked automatically and instantly in most games that supported it outside of maybe Rogue Legacy.
With the Switch, it's solving all of these issues in one motion.
To me it's not about being able to play the same games on a more competent or graphically intensive platform. It's about the convenience of being able to play in a multitude of situations. Someone else wants to use the TV? Fine! Want to get in some more game time before bed? Easy! About to go on a trip when a game you've been looking forward to on console just came out? Bring it with you.
That's pretty damn compelling to me, over graphical fidelity and smartphone gaming.