Torna was designed as an expansion and it remained one; it is not its own game, and remakes are not new games either.
I stand by most of Switch's best first party content being recycled Wii U ports, and its actual exclusive lineup being subpar by Nintendo standards.
It's a Nintendo system so that's what I'll compare it against, and when set next to their other stronger efforts it falls short thus far.
Again though, it's a long way from done hopefully so by the end of its life it may have surpassed them all, but this is why I give it an 8/10 and not a 10/10 at this date.
If I were in your perspective, I'd say the Switch blows. I mean we're looking at the following for exclusives if we leave out remakes/ports/remasters and Torna...
Super Mario Odyssey
Mario X Rabbids
Mario Tennis Aces
Super Mario Party
Kirby Star Allies
Luigi's Mansion 3
Yoshi's Crafted World
Super Mario Maker 2
Fire Emblem Three Houses
Age of Calamity
51 Worldwide Classics
Luckily for me I don't see it that way. I think Torna, Let's Go, Link's Awakening, and Xenoblade Remake should all count for something.