Was Majora's Mask ever that difficult? I played it a decent amount as a kid, but never got all that far.
Does the time limit/control aspect make things more challenging, since you can essentially fail?
You can always try again. And it's not a time limit, so much as a "structure." What I mean is, you can relive those three days an infinite number of times. And you can reset them at any time. And you can slow them down so they last twice as long each cycle, giving you two real-life hours to accomplish
something, whether it's activating a warp point, or acquiring a new item, or learning a new song. All of that is retained when you reset time.
So it really just comes down to choosing what you want to accomplish each cycle. When I played, I'd explore a new area until I reached the warp point at the entrance to the next dungeon. Then I would reset time. Now back at Day One, I'd slow down time, and warp to the entrance of the dungeon I found last time. I would then have a full two hours in real life to complete that dungeon. And time stops passing when you pause the game or talk to someone, so there's really no pressure.
If two hours isn't enough to beat the dungeon, it's probably enough time to reach the dungeon item. And that item is kept when you go back in time. So if you have to reattempt the dungeon, the dungeon item will let you bypass the first half. Meaning you now have two real-life hours to do the -second half- of the dungeon.
In other words, there's plenty of time, and no real fail state. A lot of the "pressure" in this game is imagined by people who don't quite understand how it works. But I'm confident that if someone keeps at it, they'll learn the system quickly enough.
