Largely because Microsoft and Sony shat the bed royally, and Nintendo's had the market cornered on Handhelds for years now. The Switch is terribly underpowered, and ports from other consoles show it. But because it's primarily for kids, and Nintendrones will buy anything Nintendo puts out, it's doing better than it should have.
For example, Nintendrones will gush about playing "Skyrim on the go!" and how that makes the Switch the greatest console ever, but the Switch version is quite literally the worst way to play Skyrim...and it's not even the 64-bit re-release, the Switch version runs the original 32-bit that launched on PC/360/PS3.
And it runs that version worse than the PS3...may I be forgiven for uttering their name aloud, but Kotaku released both an article and a YT video demonstrating the performance and looks of (at the time) all the different versions of Skyrim (OG PC/360/PS3, re-release PC/XB1/PS4, and Switch), and it's painfully clear that the Switch version runs worse than the PS3 release of Skyrim, and it looks to be on-par with the PC release on the lowest graphical preset.
This is pretty much true for every game released on the Switch that wasn't specifically made for it, they have to gimp the fuck out of the graphics and cut huge corners to get a game to run(ish) on the Switch...but Nintendrones don't care, as long as they can play a game "On The Go!", they're soyjaking 24/7.