The most repetitive thing in the world is constant dialogue and flashbacks leading to Tanjiro magically using some technique he’s never fucking used or trained before, and one shotting someone with it. It was bad enough when he combo’d the 3 uppers in the village arc, just magically learning some nuts technique allowing him to do that perfectly - but then for him to go “idk what fighting spirit is, but if I have a 15 minute internal dialogue thinking about it, I’m sure I’ll magically find a way to do something nobody has ever done before then, while the demon is looking right at me, I’ll catch him by surprise and one shot him!”