I get your plight. :)
Cuphead believes difficulty is automatically fun. But I don't really think the grinding this requires is fun. For me, a challenge has to feel smart and fair — I want to feel, when I die in a game, that it really was my fault.
This is a gorgeous game, and beautifully presented to boot, but without that no-one would be talking about it. Cuphead may have a classic style to its challenge, but it's not tough in the way that Contra or Mega Man were. This is more about difficulty of execution, and memorising a level's obstacles, than getting 'better' at the game.