The bigger issue for me is that the 3DS screens are just straight up bad screens. They are low res, sure but their brightness and colours are terrible too. They were several years outdated when they launched nevermind now. Nintendo cut a ton of corners in terms of quality to push their 3D gimmick which ended up being a terrible idea.I'm not sure if I agree.
I think most native res 3DS games that were built around the low resolution ( huge focus on primary colours like in MK7 /3D Land/ Animal Crossing/Fantasy Life) look outright better on a native 3DS screens than all those ghastly sub native resolution, low resolution textures Vita games.
I think the only really pretty 3D game on the Vita is Freedom Wars.
The Vita's display is objectively superior, true, but it couldn't flex it's muscles all that often imo.
Also there are plenty of pretty 3D games on Vita but i'm also not sure why you arbitrarily limit to 3D? 2D games look significantly better on Vita too.