I would hope it runs something other than BASIC. BASIC is a terrible language, and the only reason it became popular is that there was a book published with a lot of games written in that language. People buying a home computer wanted games, and the commercial game market was initially nonexistent, so people wanted a computer with BASIC, since then they assumed they could play those games. The designers of this new computer might want to restrict themselves to old hardware, but there is no reason for them to restrict themselves to that old accident of history.

Naïvely, I would assume that something like Forth or Occam would be much better for this, and both are also age-appropriate.