You're missing the point. People are disappointed Splatoon 2 looks virtually the same (graphics and resolution) because the Switch is more powerful than Wii U.

Several of the CoD games since Advanced Warfare basically look the same, but there was a huge presentation boost over last gen. While Splatoon 2 is seeing little improvments on new hardware.

Frankly, this looks like a Wii U game and people want more than that on the new hardware. Zelda atleast gave a higher resolution and people seem content with that.

they use to on the Gamecube. But they stopped with the Wii/WiiU and now Switch.

I can't stand it either... 

I'm waiting for the day Aliasing, poor framerates and popping finally disappears from video game history.

If youre playing on a 720p plasma TV there are no jaggies 

What would you have made different?

Exactly! People complain about the resolution which only might have some merit in in bullshots, but not in actual gameplay. The game is way too fast to notice.

I don't see much improvement in graphics. But hey it is about the fun, isn't it?

There are slight improvements to Splatoon 2.
Slightly higher res to textures, more details on the map, so prob a higher polycount.
You can see deformations in the ink like tracks and so on, which aren't present in the first game.

"Graphics Evolution"

Evolution is the wrong word... it basically looks the same, such a small improvement.

So basically, Nintendo is listening to the critics who reviewed the first game and they are now focusing on fixing what was wrong with it. Points were docked because of longevity concerns. Not because of mediocre graphics or low resolutions.

Keep in mind that the first was being compared to 8th generation games, hardly any critic complained about the graphics.