itch.io

Nah, don't worry, I get the struggle of finding hard stuff that is obvious to you.
I restarted and took playtest notes, hope that helps:
Screen 2, slippery, I most often than not ended on the tip or past the platforms. They're very short and do not allow leniency while you're still figuring out the slip and air control.
Screen 3, I realized that if I don't stop air control right before I land, left-right direction will be applied on landing and I will slip. Especially frustrating on the even smaller platforms while still trying to figure out where I need to stop applying directionality (direction buffers on landing are a good way to mitigate that by allowing floor grip to negate directionality for one or two frames).
Screen 4, didn't struggle but I think it's because I try-harded on it on the alpha.
Screen 5, a drop jump in tutorial is CRAZY. It's a movement that requires in-depth control and understanding of mechanics, it's absolutely not something you should throw at players this early in the game. I was never trained for it in previous screens (no platforms with similar level design but without the drop, allowing me to get used to the timing without being punished*). *By punished here I mean "failing not because of my own lack of skills, but because I don't know how it works yet" as in it's almost impossible to succeed on the first try. If it was not a playtest, I would have dropped here. I love platformers but the challenge curve is ludicrous and if I'm playing this I came for the horny, so would probably drop since no such content lured me into thinking the effort is worthwhile. Seeing a  breedable poney just above that insane jump could do the trick tbh. I detested the purple right before the challenge and died twice on it by slipping. I wanted to die because of the drop jump if I had to.
Screen 6, easy enough, with this time a timing that feels both rewarding and challenging (getting to the core content gave me a motivation boost). I had trouble understing that the gate was a platform: the shape didn't afford it.
Screen 7, the grunt I let out when the platform didn't keep moving after coming back... It moves away way too fast, comes back too fast, and with the slipping barely starting to be under control I'm unhappy with the amount of tries it took me. There are no indicators for the amount of thrusts that it takes to start it and I only fucked one poney before so the number was elusive at best. I went for spamming the controls to get it over with then jumping as soon as I could to catch the platform before it moved back. Then the up-down platform came. While what I had to do was obvious, I still slipped and missed what I anticipated to be a very easy moment, and thus realize there was also some slip on the floor, or the platform, or something else I had not understood. I made it at the second try, and was almost had by the quick move back (again, no warning, but I came to expect the worst that could happen and surely enough, it does). At this point the thrusting mechanic was not motivating anymore and I just kept going out of curiosity and playtest necessity.
Screen 8, seeing the UI change was a nice reward. I enjoyed the little piece of dialogue but was a bit disappointed that the breeding with an actual poney was shorter than with the statues. The insemination anim was so quick I barely had time to see it, and at this point I wonder whether you just made an edging game.
Screen 9, easy pass with a nice use of purple areas to guide jumps. I wished I had had something similar at the start instead of the drop fall or the moving platforms of hell.
Screen 10, hard but fun. I was starting to get a hang of the slip and chose to skip platforms 1 and 3 to have more air control. Took me 5 tries but was actually fun since I was making an active choice to go against level design while being afforded that possibility. Then I slipped from the purple mare when jumping up left and fell in the pit, and had to do it over again with much frustration, since vertical air drift is something I always struggle with (and is a very advanced skill to expect your players to have: most platformers focus on horizontal drift challenges). I went back to the purple, first rty as I knew the timing now, only to realiza that in addition to the vertical drift the platforms were not pass-through (their hitboxes apply when coming from below). I was very very close to rage quiting as it was again info I had to learn not through affordance, design or logic, but through blindly bumping against obstacles. I had lost timing at this point, failed green twice, then purple thrice (passthrough bump and fall to pit twice, slipping while trying to attempt the first platform from the left and fall to pit). Honestly, just a platform extended to the left and one less green paltform would make this so much more enjoyable.
I didn't see or find the skip tooltip, so I stopped there as my hands were starting to cramp up. For reference, they don't do that on platformers, they do that on Souls, which gave me a chuckle given your previous commentary on punitive games.

So yeah, a punitive experience through the following aspects: lack of affordance and anticipation, lack of control (especially through air and landing drift), hard to extreme challenges in quick succession with little to no breathing room between them, poor die and retry (the core of a proper die and retry is that you warn the player that something will be hard or they can deduct it by themselves in order to brace before facing the actual challenge and the death that follows; "gotcha" challenges are fun to develop but much less to play unless you know that the game is ragebait, which isn't the case here), little to no reward to foster engagement and desire to go further.