You've managed to answer all my future questions. Thank you for that.
When I refer to only the ON-CHAIN and OFF-CHAIN context, I mean in general. Maybe developers should forget about fully integrating blockchain, in your case avoiding in-game transactions so the player doesn't have to pay a fee, nobody likes that. An example of this is certainly Axie Infinity (maybe only the Origins version, the classic is a bit suspect to say that). The game runs OFF-CHAIN, although NFT upgrades can be requested in-game, there is no internal market or trading of anything during the game, just the game.