Just so you guys know [11/4]

There are way too many factors that goes into an opinion on difficulty. The 1st factor is what the player defines as difficulty. Some say it's the # of attempts while others say it's how frustrating the level is. Both are right because there's no objective way to define difficulty. The 2nd factor is what the individual player's skill is. The 3rd is how good that player is at ship, wave, etc. If someone is really good at wave but bad at ship, they might think down bass is easier than cataclysm, or that down bass is an insane demon instead of extreme and they aren't wrong.
Also, for demon ratings, there's another factor which is how they personally define an easy, medium, and hard demon. Everyone has a different definition for these things, so you shouldn't care if others say these things.