Penarium is a hateful, spiteful game that aims to make you cry. You know the types of games I'm talking about - Super Meat Boy, I Wanna Be The Guy - this game operates with the same modus operandi as those two did.
Unfortunately, Penarium often falls into the same trap the "super hard indie game designed to make YouTubers yell" genre often falls into - a lot of the difficulty isn't so much exhilarating as it is really annoying, and not just because double jumping fails to register about 20% of the time.
Here's my rule as far as difficulty goes: if you look at something and your reaction is "oh man, this is gonna be tough, can't wait" then you're doing something right. On the other hand, if you look at something and your reaction is "oh man, this looks horrendous, I'd really rather shove a cactus up my ass than have to do this", that's a problem, and that's a sadly far too common feeling in Penarium.