> There are a handful of platformers on Linux and they all have the problem of being too hard. The games in the first few levels are so hard that the player quits before they can explore what the engine can even do or find the "fun" in the game.

When you're developing a game by yourself, you play it 1000s times to test every small change, debug, etc. So you're becoming pretty good at it.

So you balance it to be challanging, and it's too hard for regular players. At least that's what happened to me.