This short review/analysis contains spoilers about the game. Stop reading if you want to have a fresh experience with the game. Everything below is my speculation, don't take them as definitive facts.
The Stanley Parable is everything and beyond video games. It's a giant commentary on todays game development philosophy. Throughout its unexpected span and twisty narrative, it has a clear message - there are problems with narrative in video games, which we have not addressed yet.
In recent years we have seen a great amount of open world/sand box games. But there hasn't been shortage in linear games with strict control over players actions. Invisible walls or direct threatening by the game if you go off the map, even in scenarios where the level design suggests more freedom than the available and, but not limited to - bugging out the whole game or level by reaching unexpected locations are common practices in multiplayer and even in singleplayer games since decades.
The layout of the office (which is briefly explained in the museum, behind the scenes room) is designed and created with the mind that the dialogue and attention span of the player would balance and lead to the first sense of conflict - the two doors.
This first dilemma is presented geniously - with a confident and calm voice. At this point the narrator is still following the hardcoded written script. Which is what I describe as the main and simple story the whole Stanely Parable is based around - there is a problem, the protagonist decides to end the tyranny of the evil force and it concludes with a happy ending.
The simple story has cartoonish elements. Toward the end of it, it cultivates exaggerated tone and willingly becomes boring, it's purpose is to show the most basic and at the same time intriguing story. But only if the player obeys/follows the steps the given by the narrator.
Not obeying the narrative, leads to all sorts of interesting results, which ultimately don't explain the whole picture of The Stanley Parable, which is left to players imagination. The game doesn't feel the need to address any of the questions which the audience asks frantically after playing it. The same happened in the demonstration, particularly in the 'Escape elevator' sequence.
Throughout the exploration/ending hunting there are many sections where the nature of narration and design in games is examined and often made fun out of.
Many actions, which are not part of the hardcoded script, of the player are directly commentated by the narrator.
Like the 'Broom closet' - this room has no place in the whole game. In traditional game narrative it would be a waste of time - there isn't a collectable or extra life and if the player decides to explore it, the game would punish him for doing so. But here, the comedic nature of TSP rewards the player for paying attention to it, even if it is only a piece of dialogue.
Achievements are another device with which the The Stanley Parable mocks the current video game industry. Take the 'Click on door 430 five times' for example - a great way to address the ridiculous amount of pointless achievements in some games. Or 'Unachievable' - an obvious phantom which doesn't have a solution. It is created solely that particular part of the player audience grinds through the game, desperately trying to get it.
So, how does The Stanley Parable get away with being so rude to every aspect in the modern video game industry, while being part of it?
Its complete and constant self awareness makes TSP simply perfect. It is written and executed exceptionally well. It deflects most of the criticism, directed at it, simply by being one.