A lot of old games have become unplayable on modern hardware and operating systems. I wrote an article about how making games open source will keep them playable far into the future.
I also discuss how making games open source could be beneficial to developers and companies.
Feedback and constructive criticism are most welcome, and in keeping with the open source spirit, I will give you credit if I make any edits based on your feedback.
Apps are challenging to preserve, but it’s the MMORPGs and online games that are almost impossible since there is no game without active servers and people playing the game. Hardware can be emulated and code preserved, so the apps you’re talking about could be preserved IF Apple, Google et al wanted to - which of course probably won’t happen, but still.