The NES library was directly responsible for re-introducing video games into both the American and Japanese mainstream.
The Gameboy's library was the basis upon which the very concept of handheld gaming was effectively built.
The SNES is considered by many to be the all-time greatest gaming library ever.
The DS had basically all the highlights of the 3DS taken to 11.
The 3DS falls into the same niche as the N64, Gamecube, and to a lesser extent the Wii U. Strong first party support, a few 3rd party standouts, but the list of truly great games gets shallow really quickly.
It's a great litmus test for how firmly someone view the world through rose tinted glasses though.
Kid Icarus is an outright failure in handheld game design beyond even the MonHun claw grip on PSP levels and yet people in this thread are claiming it's an all-time great title.
DQ8 is an across the board presentation downgrade one what remains one of the best audio-visual JRPG experiences out there, but "Quality of Life" things like no random battles make it better? I'm sorry but when did random battles become an inherently bad thing in a JRPG?
And the 3DS popularization of Fire Emblem came at the expense of what many fans liked about the franchise (meaningful strategic choice) and at the same time effectively killed another great franchise in Advance Wars. No AW is one hell of a black mark.
The very OP of this thread in both text and in the game image included effectively touts inferior versions of multi-plat games as a highlight with Steamworld Dig, Snake Eater, Mario Maker, SFIV, Virtue's Last Reward, etc..
The 3DS lives in a very specific niche. If you like a blend of Nintendo first party titles and the traditional Japanese handheld IPs (MonHun, Etrian Odyssey, Layton, Wright) it has value. I personally do but I'm not about to argue it remotely compares to the DS or SNES in overall library. It is more comparable to the PSP and the GBA, the later largely a product of it's incredibly short lifespan.