When I ran 5e, I felt like I was fighting the system itself in order to run any kind of campaign through it, as characters had too many special powers and abilities that would obviate any challenge I attempted to put before them.

I had the same feeling while running AD&D 1e, that I was fighting the system itself, but for different reasons. 1e contains so many little issues, edge cases, and many of the rules are open to interpretation that I felt more time was spent navigating around issues with the rules rather than actually playing the game.