It's not complicated. It's just there is no other game like it. Therefore no one can relate to it. In Counter-Strike, you know exaclty how to reload the gun, and shoot it, and how to move and jump and crouch with no prior knowledge.
In E.S.F, you have to actually learn how to swoop. Learn how to do combos, or how to knock someone back twice. Or how to engage in advanced melee and know how to punch, kick, do combos, or throw someone. People ask "How do you play?" because no one can relate to any other game to figure it out. And no one reads the manual because it can be difficult to find, or just don't like reading. I myself would rather learn by playing. That's how I learn, but I read manuals to get an idea on what I'm doing first.
For example. Natural Selection. I played that for the first time in my life last night. But it's no ordinary first person shooter. Sure, I knew how to shoot, reload, and I learned quickly how to upgrade myself for higher defense, different weapons etc. But what I didn't know, is that it's also got an RTS version of it where a commander tells you to do things, and can get very tactical. And although I play RTS games, I've never played an RTS/FPS game before, so it was a very new experience to me. Hence difficult. But it's nothing a little practice won't handle.
People just need to take a couple of hours or maybe days to learn the style. It's not that hard to just sit down and get used to it.