I would never, of course, make such a broad claim as that Fossil Fighters is the best game on the DS (that's Freshly-Picked Tingle's Rosy Rupeeland, obviously). It is, however, the fullest demonstration and justification for the DS' unique control scheme and features. So many games either had utterly unnecessary touch controls (e.g. New Super Mario Bros.) or barely made use of the touch screen at all (e.g The Legendary Starfy [5]). But Fossil Fighters, designed from the start around the unqiue affordances of the DS, centered itself around a minigame where you hammered and drilled away at a fossil with the touch screen, and then removed the resultant dust with the microphone.* As anyone who has tried using an emulator will tell you, this minigame simply does not work as well on any other format. Using a mouse both hurts your hand and makes it harder to move around quickly, while using your finger obscures far more of the screen than was intended. Even more than that, you lose that tactility of holding an actual implement in your hand. In particular, as someone who played the game with the sound off for years, the fact that the stylus makes a...somewhat hammer-like tapping, and...okay it scraping around doesn't sound anything like a drill lol. But still, it makes a noise! It correlates! The best part, though, is that the cleaning minigame is simply fun. There are all sorts of rock shapes, and fossil shapes, and levels of fragility, every one involving at least a little planning. Consider how in other RPGs you make your party members better by tedious grinding, over and over and over again, no thought or effort; the only obstacle is patience. In Fossil Fighters, on the other hand, to increase your vivosaurs' stats, you have to get better at cleaning. Or just drop the fossils off at KL-33N, no fee, no penalty, no judgement. Fossil Fighters is chill like that.
*Thankfully from an accessibility standpoint, you can also clear dust with the L or R buttons.