That's completely fair. I think making a tough game is great, and after adjusting to it I got the hang of it and really enjoyed it, but I think it was more so the level design that's confusing at first.
When I got to the first tough jump after the thin beam in the first level, as the jump was so precise, I thought that I was doing something wrong or I was missing a mechanic, as the rest of the jumps weren't near as precise. After trying a few more times, I realized I just had to delay my jump super late, and once I learned that, I realized what the game was and what all the rest of the jumps were going forward. Having that jump is completely fine, but I think having it far away from the checkpoint makes the player question why they're having such a hard time with a jump that in their mind, is just another jump, when they haven't been taught that the game has precise and challenging jumps up until that point.
Then after doing that jump, getting bounced in the air and having to control the players movement in the air, I had no reference to how the momentum of the player worked while in the air, and had to get the hang of it on the fly. If I messed up or didn't understand the way they moved or carried their momentum properly, I had to recollect the item, and do a really tough jump again, to get another shot at learning how to move in the air again.
TLDR: it felt like I was being tested on movement, jumps and mechanics that I hadn't learned about before hand. Some kind of introduction or subtle level design could turn around all the confusion of the difficulty and make it work in the games benefit. When you have playtested and adjusted to the movement while making the game, you don't need an introduction to do the tougher jumps/movements, because you've technically already had it. Other people playtesting can go a long way in this case.
sorry for the long reply, i just think this game has a lot of potential and don't want people's experience of it to be put off by the tough first level😅