Blast from the past indeed! I ve toyed around with it, Ogre3D and others, finally setting down on P3D. Over a decade ago I maintained unofficial Panda3D Facebook page, and had page analytics track followers count again Ogre3D and Irrlicht Engine pages, trying to surpass them..
As someone who often sees personal collections scathered around in the dust of flea markets, I would say there is nothing you can actually do to be safe. Even if your kids preserve it, their kids will _pay_ local gypsies to take it all away so they can renovate the houses and flats. From there it's as good as trash.
I mean I like duckdb but this feels like you're pushing for it. On my system postgis comes from apt install, and it's one command to activate the "plugin". Is the night and day part not having to run random sh script from the internet to install software on my system?
Put him on debian stable with xfce and no sudo if he is such a bother. Sounds to me this is a people problem, not Linux problem. Do you miss windows or do you miss not having to spend time with kid on things that bother you?