I agree and disagree on some of your points.
While I also have the impression that many people indeed use the expression "Walking Sim" just as a derogatory term for "game which I don't like", I think it is a valid game category.
Of course, you can't 100% press a game into it (same as every other game type). There are almost every time some elements which belong to a different genre.
I only discuss the games of your list, I know.
- What Remains of Edith Finch. - first person adventure game.
Disagree, this is a walking sim.
While the basic interactions and variety is really creative and this game IS the best walking simulator around, the possibilities to really do anything are extremely limited and there is only one linear path.
Even in "The Vanishing of Ethan Carter", which you list as Walking Sim later, there is much more to do and it is less linear than this.
- The Council - adventure game with light RPG (?) elements.
Agree
- Life is Strange - classical adventure game.
Mixed: While I agree, that this is not a Walking Sim, it definitely isn't a classic adventure either.
- Everybody Gone to the Rapture - probably the only real "walking sim" in this list, with very light single "puzzle" mechanics.
Agree, but not the only one
- The Last of Us - wtf is this even doing here
Agree
- Stanley Parable - more like very ironical narrative puzzle game...this game is amazing whatever you call it, play it anyway at least two times,
Agree
- Talos Principle - narrative puzzle game
Agree
- The Vanishing of Ethan Carter - yes, more or less walking sim
Mixed: This game is on the borderline between Adventure and Walking Sim. Contrary to other games of this genre, it actually has some puzzles and exploration. So you could count in both areas.
- Firewatch - first person adventure game which, yes. involves a lot of walking.
Disagree: This is a classical Walking Sim. While at some points there are slightly alternative paths you can "walk", the game is otherwise very linear with minimum optional exploration.
- GRIS - I guess yes, it is walking sim (side scroller one)
Disagree: This is (very easy - but still) platformer.
- Dear Esther - father and mother of the genre
Agree
- Mind: Path to Thalamus - walking psychedelic sim and not really a good one
Definitely disagree:
Please, play the game first a little more before judging it. You obviously only played (the admittedly very long) intro.
As I mentioned in another post before, this game has lots of puzzles later on and even features some kind of bossfight.
And the later puzzles are not extremely "walking through" easy, you actually have to think a little bit in order to solve these.
In general, the puzzles in this game are quite more difficult than the majority of puzzle of the other games in this list
(Right of the bat, I only see The Talos Principle as more difficult puzzle-wise than Mind: path to Thalamus.)
Yes, the story of this game is shit, but that has nothing today with the gameplay or genre.