I do have a fold 4, and can say it's decent as a 2DS, but it was 1200 dollars. A Quest 3 with Citra VR is 3DS, not just 2DS, for 500 dollars. Full functionality. Smooth 1080p on most games, higher on some, lower on others. You can set the 3D depth, also there is a fun option of playing some games in first person 360° immersive VR. Kind of fun to be able to "exist" inside the world of the games you played as a kid, or... younger adult..... or in some cases the games your parents played and showed you when you got old enough to want a portable device, but young enough that your parents wanted it to be something cheap and durable.

Footnote: Using the d-pad in Citra VR is not obvious, just place your thumb on the rest pad of either controller and the other controllers joystick becomes the d-pad. It's not as complicated as it sounds, it feels pretty intuitive once you do it a couple times.