I should probably give KSP a try again. I guess there's an initial threshold I got to power through first, as I got a bit exhausted after the first mission hehe.
I'm actually working now on a game of my own, with themes of science, and it's indeed a game-first approach rather than an educational game, but I do hope to maybe inspire some ideas and motivation with at least a few players.
I totally believe there's a lot of untapped potential in this area, and advancing towards cracking learning motivation + capabilities could have a huge impact.