Nintendo should just lower the FPS per second in order to get the resolution up to a stable 900p. In what world do you need 60 FPS for a relaxing platformer like Yoshi?

The games art/texturing/geometry isn't particularly noisy/complex it's simple, it's clean... And that means it will hold up better at lower resolutions as there are less edges for staircasing.
That's not a bad thing either.

It's a case of using better art assets to make your limited resources go farther.

I don't think the CPU is what holds back the Switch most of the time either.
ARM A57 is getting old (5+ years) and the Switch only has 3x CPU cores available for games and they only clock at 1Ghz... But they can still pull their weight... Being a 3-wide design unlike the narrower 2-wide with the Jaguars certainly help matters, that's for sure.

The GPU is still clearly the biggest hindrance followed by memory bandwidth... Especially for newer engines which are pushing an array of effects.
Maxwell is efficient sure, much more so than AMD's efforts and is punching above it's weight... But it just lacks the resources to drive home those resolutions... It just doesn't have the fillrate.

Give me 60fps over hd resolution any day of the week. This game looks great thanks to the smoothness of its framerate.

Agreed, I had a similar discussion with someone before. In a nutshell he said the CPU and GPU of X1 and PS4 weren't well balanced compared to the Switch, but I believe the opposite.

I used Ark as an example because that game runs surprisingly okay on Switch, even with many dinosaur models on screen, flying over the world, etc. There isn't a CPU problem on Switch per se, developers are struggling with its limited GPU.

With this game, considering its running 60 fps with UE4, it shows the Switch CPU is actually pretty good. While the resolution could probably be 1080p with GPU power equal to X1.

Like I always say, quality of pixels > quantity of pixels.

Good Feel made the right choice here prioritizing a smooth 60fps and those gorgeous materials over a higher resolution. Honestly, if you hadn't told me it was 675p-576p I wouldn't have known, it's still one of the most beautiful games I've ever laid eyes on.

This is a new graphical high water mark for Unreal 4 on the platform, and it will be interesting to see how other UE4 Switch games later this year like Dragon Quest 11, Mortal Kombat 11, Claybook, and Hellblade shape up. The engine could really be starting to come into its own on the Switch.

Is that figurative or are you being literal? 

Well, in the sense that I'd prefer 675p with lusher visuals over 900p with sparser, blander graphics.

Oh ok. I think it's a little bit more confusing when you say "pixels" instead of just the visual presentation though   But I see what you mean. 

Unreal Engine 4 strikes again! I wonder who will be it's next victim ...

While it is surprising to see how low the resolution actually goes, the game looks really great for that. I did notice bluriness in handheld, but not to a degree that it made it less fun. Still I hope the final release or patches afterwards will increase the resolution performance a bit more.