You can sit a 5 year old in front of all sorts of games that they'd enjoy, but Mario and Pokemon is what they've been exposed to, by you or friends or both. You'll have a difficult time arguing with them over the importance of how your individual market actions have lasting effects on what gets produced; that's true. But Nintendo only has a monopoly on marketing kid-friendly games, not producing them...not that that will matter to your 5 year old.
As for preservation, server dependencies are bad. F-Zero 99 requires a server and a subscription to be played, full stop. That game will not survive, and other battle royales or even other "99" games are already being decommissioned and will cease to exist. Online multiplayer can still exist without server dependencies, via private servers or LAN or direct IP connection; these features are becoming increasingly rare for business reasons, so keep your eye out for them. Without these features, multiplayer will disappear at some point. DRM is bad. While it often doesn't bother people who purchase legitimately, sometimes it does, including long after the initial release period, if that DRM hasn't been patched out, because the company authorizing the DRM usually doesn't care about the repercussions of it two decades from now. Baldur's Gate 3, not a game to play with your 5 year old for at least another decade, has all of those multiplayer features and is available DRM-free. BG3 will be preserved. The gold standard for preservation is open source, where anyone can view the code and change it, which means it will always run on whatever computers we use in the future. This is why Doom is ported to everything with a screen and an input device. But open sourcing your game is a hard sell for developers.