What boggles my mind is how someone could sit down at any game, I don't care what kind of game it is, and expect to play without learning how.
My guess is that for some players, there is an expectation (perhaps based on how the game was presented to them) that it is just "make believe with rules", and that they can concentrate on the make believe part while someone else (typically the GM) handles the rules side.
This approach won't work for any game that expects the players to engage the fiction via the mechanics. Formally, then, it won't work for any RPG! But in practice there is an approach to RPGing - in D&D, I would say it was especially prevalent in some 2nd ed AD&D play - that regards the mechanics as secondary, or as simply an aid to visualisation/immersion, with the real resolution work happening in the fiction as mediated through the GM's judgement. The canonical form of words for signalling that one is playing in this style is "We had a great session: we didn't even roll the dice once!"
I'm personally not a big fan of that approach, because of the degree of GM force in resolution that it presupposes and relies upon.
EDIT: Consider the "prone" condition. In 3E, this soaks a move action to get rid of a severe debuff, and triggers an OA as a result. In 4e, this soaks a move action to get rid of a modest debuff. In D&Dnext, this soaks 5' of move (out of a typical 30') to get rid of a modest debuff.
So the tactical significance of knocking a foe prone is quite different in each system - it is most punishing in 3E (except that it doesn't establish sneak attack vulnerability) and least punishing in D&Dnext.
Nevertheless, I believe that there is a type of player who is really not interested in those differences, and who decides whether or not to devote action resolution resources to knocking a foe prone on quite a different basis. (Roughly, the "colour".)
The same sort of player, presumably, doesn't worry too much about learning the minutiae of his/her PC sheet.
And before we deride such a player too much, let's consider that James Wyatt is perhaps such a player. As per his latest
Wandering Monster column, he says that
Orcs fight fiercely and hit hard. In the [playtest] bestiary, they wield greataxes to dish out heavy damage, and they can augment their damage with their Rage trait.
In fact, though, using their Rage trait will actually
lower an orc's damage output unless the target's AC is ridiculously low (less than 11, or less than 15 if the orc would have advantage but for Raging) or unless the orc is already suffering disadvantage (maths on
this thread, posts 32 and on).
So Wyatt seems to be in the "colour over mechanics" camp too!