This is a really nice idea. Which is refreshing, because my go-to is always something mildly disturbing but not too scary or criminal.
If I were going the wholesome route, I’d add a paper note to the USB or other digital storage, though. If I were to find a LaserDisc from 1990, that would be more or less unreadable without expending some significant effort.
But maybe future folk will have magical devices that can read cassettes, 8-tracks, or whatever.
it could use a couple of peepholes and an escape hatch. Otherwise, a solid fort.