Gris is a hard game to recommend because, while it is a game, it doesn’t really do anything particularly unusual for a game. The platforming is passable and there really isn’t a narrative in the sense of the game telling you what is happening. If you go into it expecting a game it will be disappointing or at least just ok.
Instead, if you go into it expecting a visual and audio journey through the emotional prossessing of grief, and growing to move forward, it is incredible. Especially if you happen to play it while working through your own grief.
People who recommend it need to provide a caveat that it is less the game mechanics and more the emotional journey.