I REALLY often get into that mindset. When you develop you playtest SO MUCH you get so good at the game, and for me it often leads to thinking "oh, game is too easy, no-one is going to enjoy that". Then I end up cranking the difficulty so much (or adding new mechanics) it becomes impossible for anyone to even start playing.
OR when you know what you're supposed to do, all items locations, etc you start thinking "my game is 5 minute long I need to make it longer". While new player struggle in it for 2 hours with just basic bearings.