Alan Wake 2 had a very high MC score. It didn’t sell as much as any modern Resident Evil title.
Alan Wake 2, with its 50M development budget, isn't a AAA game by today's standards, and it shows by how uninteresting all pre-release materials representative of actual gameplay looked. There wasn't any equivalent to The Last Of Us Part II's E3 2018 trailer that sold the audiences on a gameplay experience either of an originality or a level of refinement they've never seen before - which is the essence of real AAA titles.
It's clear that Remedy poured all of their resources onto the story and the delivery of their ambitious narrative, but due to its limited resources, Alan Wake 2's gameplay wasn't anything special, didn't bring much to the table (not only for the survival horror genre, but also in contrast to the original) and couldn't match the level of refinement in the mechanics of its competitors.
To someone that isn't familiar with Sam Lake's chops as a storyteller, the pre-release materials of Alan Wake 2 simply didn't say anything to them. On the other hand, the promotional campaign of Resident Evil 4 grabbed everyone's attention with that impressive gameplay walkthrough of the initial village area, where enemies would ambush Leon from everywhere. That's an example of a fresh gameplay scenario that draws interest towards your game, and what Alan Wake 2 lacked.
On top of that, the game didn't have a physical edition nor a Steam release, and was launched with minimal marketing in between Spider-Man 2, Mario Wonder and Call of Duty.
No wonder why it didn't set the world on fire.