I just finished playing through Ocarina of Time's notoriously challenging dungeon, the Water Temple. From what I've heard from people in gaming communities, it's one of the most difficult stages in the puzzle platforming genre. Some people even consider it the hardest dungeon they've ever played.
I can somewhat relate to the general sentiments about this particular area in OoT. Most of this dungeon's puzzles use precision shooting + timed triggers, and aiming with a controller isn't really one of my greatest points. This was the only thing that really bothered me about the WT, being someone who is mostly unfamiliar with using a console controller. So far I had to begrudgingly deal with high stick sensitivity when using ranged weaponry. I barely managed to finish the shooting range challenge; It may take some time (maybe never) for me to complete the horseback archery challenge. You also had to shift between gear a lot in this dungeon. If you barely paused or opened the menu so far, you'd be seeing it more frequently.
Overall, I don't really think the dungeon is exceedingly difficult. I actually found it to be fun to play through. Maybe because I think the Iron Boots are cool, but also because the level design was something fresh for me. Back when I was still in grade school I mostly just watched my older brother play through LoZ: OoT, but I don't recall him getting stuck or ragequitting because of the Water Temple. The dungeon itself is very much playable, although saying it was way too easy would be a lie. Still, WT can't hold a candle to the mind-bendingly grating Meat Circus level in Psychonauts.