The original point was that RPGs have a problem with streamlining what they expect the players to do, as opposed to adventure games - the LucasArts model was for a long time prevalent in the industry and nowadays there are very few games in the vain of the Sierra model, which is indeed fuzzier and less focused on what the LucasArts model perceives as the absolute essence of adventure gaming - namely puzzles, being far removed from notions of danger and reflexes in favour of intellectual challenge
I don’t know if you are right about LucasArts model, but lets’ suppose that for the sake of argument. There are many reasons why the distillation of the essence of adventure games is easily achievable:
(1) First, you don’t need to play other adventure games to get acquainted with a new adventure game, but you need to play other cRPGs, or at least have a notion of what is character building, to get into a cRPG.
(2) The puzzle elements of an adventure game are easily presentable, the use of skills and stats in cRPGs are widespread in a bigger game world; build combinations are not always intuitive, etc.
This explains why adventure game puzzles have a low entry bar, but complex character building is a high entry bar.
I don’t think that the perception most developers have about cRPGs is fuzzy. Rather, I think they are either incompetent because the systems are more complicated, or desperate to attract more players by streamlining them, or because they are knowingly making superficial action games and labelling them as cRPGs – see posts above about avoiding competition.
It seems to me that cRPGs should provide a variety of choices to surpass obstacles in the form of combat, exploration, dialogues, etc. (choice and consequences), and these choices are restricted by abstract models that represent attribute and skills (character building).
Some players are resented about recent cRPGs focus on narrative and dialogue because these games have fluffy character building and bad combat. But this is correlation, not causation. The problem is not the increasing importance attributed to these game elements, but the lack of importance attributed to character building, which govern every gameplay element, including choices and combat. This explains the paradox that some combat centric games seem to be more genuine cRPGs than games that have more focus on consequences or are more reactive.
The reason why character building is increasingly fluffy is that (1) most developers don’t know how to make a proper character building, (2) most players don’t expect this (or don’t enjoy this) because they used to play superficial action games labelled as cRPGs, which puts more pressure on developers to streamline everything, etc.
Storyfags that don’t understand character building are not alone. They have the illustrious company of “cRPG” players that think that Diablo is the essence of cRPGs. Instead of teaching new players how the joy of mastering character building, we are streamlining everything. It is like labelling checkers as chess, because most people hate chess and most developers are bad chess players. Now, let's put geometric shapes, because numbers are so intimidating, and forget about the math of character building while focusing on psychology.