The other ports are completely fine graphically when playing handheld. I think because this Lego game seems a big step up compared to the earlier ones it's struggling to cope completely on old hardware. I think updates should hopefully improve it though. I've read that it's better when playing on TV.
I believe the developers rewrote the game engine for this one, and it is a lot nicer graphically, so it's no surprise the Switch isn't the best platform to play it on. I'm going to wait for a Steam sale and pick it on for PC.
The best Lego game on the switch is still Lego City Undercover, I reckon. Most disappointing is Marvel Superheroes 2, and I must admit I've bought a couple in sales I've yet to play, despite these being some of my favourites to play a few years back, especially in multi-player with my wife and kids.
It'd be nice if they bundled up the now-defunct Lego Dimensions stuff and just made all the characters unlockable, because there was some really good stuff on that.