The whole point of the game is to be as difficult as it is, but I think EK also makes the difficulty really natural compared to a bunch of badly designed hacks like Dark Rising etc. Most of the difficulty of EK other than its excellent opposing trainer rosters comes from removing advantages that the player normally has over the AI, compared to just making you fight a bunch of overleveled mons. For example, the AI doesn't know how to use things like setup moves or weather moves or protect effectively, so the player isn't allowed to use them to get an advantage. Also, the player doesn't gain EVs because its impossible for the AI to have them. Its things like these that make me really like EK even though I would never attempt a nuzlocke of it myself