Most of the game discs that ship today don’t have the full game bundled and require Day 1 updates. Impossible to preserve these games just with emulation if the game servers are shut down.
My only real frame of reference on this is the Wii U (https://wiiu.hacks.guide), but for that platform, it's absolutely trivial to either dump them from a console or even pull them directly from the original Nintendo servers (which won't be there forever of course, but you only have to pull them once for the purposes of archival).
Of course there's exceptions. Animal Crossing New Horizons dripped its content out over the course of 20 months. I'm not sure if recently minted copies come with updates on the cartridge.