Cartridges mean nothing to me. If I want to play something old I pirate it, and phone hardware has advanced to the point where you can get used phones from a generation or two ago for not much, slap a phone controller to it, and now you have a handheld that can play anything retro, but also 3ds/wii/GameCube/some PS2 titles even/I guess Dreamcast too. It probably won't be long until phones are capable of switch emulation either.
I know that doesn't mean much to people who like physical disks and whatnot, but personally I don't see the value in collecting stuff in some kind of funko-pop gamer consumer aesthetic. Also, emulation gives you the opportunity to upscale the games you play. I just did radiant historia at 4x upscale with a ai-upscaled texture pack on my phone and it was a huge improvement.