Skills as Barriers to Games

Skill or Mental Models as Brain apps
The thing about Load Bearing Gear, Logistics, and any Mental Model is that its kinda a skill when it comes to TRPGs. By skill I mean: One has understood it to a point that they can recall a lot of key details about the matter without much load to their working memory Or ones conjures the Mental Model (imagine it as an app that starts running in your brain) that will deal with: Travel Mechanics, Trade mechanics, Personality mechanics, etc.... working with the example of load baring gear: the more you tackle and handle load bearing gear the more intimate and ingrained the knowledge becomes. Almost without much effort you realize and constrain your options and actions based on the Opportunities and Constraints of the Load Bearing Gear (or what every Mental Model you've conjured).

Which provokes a kind of discussion about TRPG running/playing games skills (which Id like to further discuss in a Gdoc):

Hypothesis/Claim: Some games or styles of play are harder and more complicated because they require some Skill or Mental Models to run smoothly (or run with a Good User Experience). 

Are these Barriers to certain Games? Is it why people hate these kinds of game, are theyre just experiencing the Skill Learning Curve to a certain game, are they experiencing the ambiguity of uncertainty from not really mastering the skill (or having no one to feedback to help them improve)?

An example of mental model: The Constraints and Goals/Opportunity Model.
An Inspiration from Work and in Games (can't tell anymore) is Goals and Constraints Mnemonic.  So basically in any project of so much complexity that our working memory needs anchors and tests to know if we are headed the right direction there are Goals and Constraints by which we can check our progress. There is a Skill involved in crafting Goals and Constraints as well as conditioning so that when Our attention and focus realized an amount of time or work has passed we go back and check on these navigation guides. This becomes a skill when the person can always rattle out all the Constraints and Goals at any point of time: they have a working memory slot to be able to hold the constraints and goals to be able to use it periodically.

I learned this in TRPGs and further developed it in work. Basically I realized that when I role-play I adopt the Goals and COnstraints of my Character. These are in the form of the characters SWOT, his personal history and psychology. You do RPGs enough that we get into character quite easily and quickly - but to take it further is to use this technique in Navigating Projects of complexity that we can only take small bites or bits of the Project at a time and process them with our working memory.