I have been playing recently, for obvious reasons of it being removed and having just bought it, I'm somewhat a fan gameplay wise. Tho, I have noticed that the game looks graphically mediocre for several reasons:

The lighting engine is barely passible.

Polygon models are comparatively coarse/low-detail, even for games of similar time period. Terrain is even worse.

Implementation of contact shadows is incredibly lackluster. (if I am understanding the concept of SSAO correctly, if I am not, ignore this point.)

Textures are abnormally low-resolution, and badly covered up with mipmapping (or some eqivelent).

Are these actually legitimate? Or am I just not understanding some form of buget to relative-graphical-quality ratio? What are your thoughts on the subject? The reason why I ask is because I am comparing this to games such as Metro 2033 (of which is known for absurd grapical fidelity, 2014), and Mirror's Edge (2009), of which may be massively inflating my view of how games in 2012 looked.

I just feel that the game looks like something from 2006-'09 in my eyes. Seeing where we came from, System Shock 2 (A bit of an extreme example, but it makes my point, 1999), and so on; a game made in 2012 should look far better than this.

It was made for consoles and if the developers made minimal effort to improve the graphics for pc, that shows. At least they polished the gameplay on pc, if others are to believe as I did not install this yet.

Now you are way above my knowledge. All I know about tesselation is that it was introduced in DirectX 11.

-----
I will finish Metro 2033 (the game, 2 books finished) before installing Alan Wake...

I haven't played Alan Wake since finishing it shortly after its Steam release in 2012. I can certainly agree that it felt like it was showing some age even then. But I went into it knowing that would be the case. Not only was it ported from an Xbox 360 release that was itself already a couple of years old, but it was also a game that had had a difficult development process that delayed its release even on the 360 by quite some time. That 2012 date belies its much older pedigree. Sure, I might have wished for a more technically adept game, but it is what it is. Personally I think it does a great job of working within its limitations to still set a tone that very much appealed to me.

But what do I know? In the last year I've played through both Turok remasters, and those still have textures that show the game's N64 roots. So I simply may not be the most demanding of audiences.

As for injecting tesselation, I'm no programmer, but I highly doubt you can mess with vertices in a game in any reasonable way through code injection. Not without introducing all sorts of major problems.

Thanks for the info.