I didn't read past the 4 or 5th paragraph, but I'll give you the reason: Gamers are afraid of Easy Mode because you alwaaaaays have an excuse for getting killed on the hardest level.

You've got skill. But there is such thing as sheer dumb luck that makes you step out from behind that building at exactly the right (wrong?) instance and you get taken out by that sniper. If you're playing on Easy, that's just embarrassing. Same scenario on "Legendary" and you've got a good excuse :)