Every time I play a game that is actually trying to be hard and see people complaining about difficulty makes me think I'm either really patient or just better at videogames than what I think I am. Either way, nice little game, took me 20 minutes.
There's a difference, I think, between a game that is hard to master and a game that is hard to control. I also finished in just under 20 mins with 349 deaths, but sections of this are made painful by the level of precision that is required from floaty controls, ungenerous hitboxes and the weird effect of ceiling collision. The design challenge of making a hard game is how to make its difficulty fair so that improvement is meaningfully differentiated from luck.
I personally like challenging platformers. I think some people are just less patient, my sister struggles with platformers and gets frustrated. I finished in 14:54, all items collected and 225 deaths.The only platformer that's really annoyed me is New Super Mario Bros. for the Nintendo DS, there are just some insanely tough levels and it really annoys me that if you lose all your lives you have to restart from the last castle. Maybe Mario isn't a bad series, I just had a bad introduction. But that's the only Mario game I've played.