I think the lack of any explicit game mechanics involved with the gameplay is exactly what makes the design brilliant. The interactivity of a typical videogame investigation is just busywork. Find all the objects in a scene you can interact with, and be rewarded with some “ooh who found a clue, who’s a good boy?” condescension. Fuck that. In Obra Dinn you decide what’s a clue and what’s important, and it’s just so much more satisfying.
I wrote about this at some more length in the Detective Games thread, just since that’s where I’m collecting all the different ways the problems of investigation / deduction are solved in games:
