This phenomenal adventure receives only good reviews and the Metascore based on 65 critics is 82.
One of the newest critic is from Gamespot saying that the game is unpredictable but still deeply cohesive. The Vanishing of Ethan Carter needs a second play through the game because after you will finish it for the first time many information will not fit into place and you would like to pick all of them to understand everything.
"There's a thematic bond that ties the whole thing together, from the run-down state of each building to the picturesque views that provide a vague sense of hope in the face of all this decay."
Of course there are faults in the game but not big ones. For example not very well working save system or missing logbook which would help in the progress because often many conversations in the past are not in your head anymore and you must go back in order to replay them.
"The Vanishing of Ethan Carter is a stirring tale that walks a fine line between the human and the supernatural. As the layers begin to peel back, what you'll find is a story told with a level of cleverness and elegance rarely seen in games. It confirms the feeling you had from the first breathtaking view; when you enter into Red Creek Valley, you're in for something special."
You can also take a look here to see that all the major critics are above 80/100, mostly even 90 and more.