Yeah, this is the real underlying reason why 4e is so well-liked (particularly in retrospect) in a large segment of the community. Because the FIRST THING that happened when it was designed is someone said "this is a game" and all the weird 'but it has to be realistic' crippling thinking went out the window. What you need in an RPG is 'story thinking', what will make a game that plays a good fun story, both in outcome and process. One aspect of that is that we can understand what is going on and the fiction has some 'bite' to it. So we do want a sort of map of expectations, which are ultimately derived from actual human experience in the real world, to exist between the fiction and the way the game process interacts with it and how that whole interplay works.
What we don't want is "that isn't realistic, so you can't do it." That's what mother nature tells me in the real world, which is exactly why I play RPGs. There was more to it than just this aspect, but you often see this part raise its ugly head when people talk about weapons or something like that. In terms of the 'trident vs sword', I guess you could argue that the rules should favor swords, but you can equally well argue that should be up to the players. It is of course logically impossible for a single game to cater to both wishes...