You have an opportunity. Give him a pre-installed Linux and a terminal, along with a page of commands that he can run to do neat things… including starting the GUI to watch his favourite (ideally pre-downloaded) videos, running some demos, etc.
Don’t make it too easy, but not too hard (2 you said? Can type a few characters though…)… Add to it over the years, unlocking the power, and guiding him to discover more by himself.
Kids won’t become tech savvy if we hand everything to them on a silver platter, with touch screens, controllers, and flashy games. It can be bland and boring, until they do something.
It might just be the most life changing gift they ever receive.
Nokia Jaws was the best.