The Nintendo Store goes down in ten years, and you're shit out of luck.
People on this thread are talking about playing Super Mario 64 because they own their game. Nintendo has been ensuring you will not pass down your games to your children.
No first-party game is a Game Key Card and without them, the rest of them would just be digital without a store-release. No store has yet shut down, you can still download bought games from the Wii Shop from 20 years ago. And GKC aren't tied to the eShop infrastructure. Nintendo did the least damaging thing while still giving gamers the option.
Two wrongs don't make a right, but three wrongs also don't make it right, it just makes Nintendo last. If anything, it proves the market will bear it, and the only people who really care about actually owning a game are those who have done it before.