Estragon and Santiago do nothing
I'm a sucker for a story about nothing. The cult status of movies like The Big Lebowski and Clerks are probably a good indicator that there's a lot of fans of movies about nothing too. Small stories where the world doesn't hang in the balance are often more emotionally accessible, but some stories really seem like there's nothing that happens at all. I just read a tattered old library copy of Waiting for Godot that one of the previous readers had jotted all their notes all over. There was just about as much ink from their bic pen as there was from the publisher. It was an interesting and informative experience to read the thoughts of someone else at the very point they are inspired by the story. The reader had interpreted the story to be entirely metaphorical for christian themes and had taken great pains to figure out exactly which character was acting as the Christ analogy on each page. Waiting for Godot is famously ambiguous and has been interpreted in dozens of different frameworks. Maybe it's because the story has so little, that we are able to read so much into it. Didi and Gogo do almost nothing, and in the second act, they do nothing all over again. There isn't any character development or clever plot twists, just some pathos, existentialism and a carrot. When I pulled the copy off the library shelf, I noted that just to the left was a dozen or so books about the philosophy of Simone de Beauvior and just to the right of it was maybe three dozen books offering interpretations of Waiting for Godot itself. De Beauvior left no mystery about what her ideas were, but Beckett not only was intentionally ambiguous, but for the rest of his life he refused to comment on the meanings and themes of his play. Why should we write three times more about a play with nothing in it, than about the profound and brilliant ideas of a leading philosopher? Perhaps we just can't help but fill in the blanks. We love a mystery. Waiting for Godot is a story with some obvious and undeniable emotional weight, and characters who must have fascinating histories, but we aren't privy to anything beyond what happens on the stage. However you interpret the story, you're implicitly confirming that there is something that happened before the curtain lifted to make those characters so interesting, or that there is some deeper hidden themes that Beckett was exploring.
Another example of a short literary masterpiece that is broadly interpreted is Hemingway's The Old Man and the Sea. While my copy of this book isn't a tattered and defiled library copy but a very fancy heirloom edition that was gifted to me by my mother. It bears no ink from anyone else's pen, but I have read numerous (and sometimes equally religious) interpretations of the novella. The plot is almost as stripped down as in Godot: Santiago catches a fish. The cast of characters is just as few in number but also just as rich in implied backstory. Readers have loved to imagine Santiago fighting against the great fish as a metaphor for any number of other struggles in their own lives, and critics have developed elaborate frameworks and analyses to explain each element in the story. Hemingway, unlike Beckett, let slip his 'secret' behind his story: "Then there is the other secret. There isn't any symbolysm [sic]. The sea is the sea. The old man is an old man. The boy is a boy and the fish is a fish. The shark are all sharks no better and no worse. All the symbolism that people say is shit. What goes beyond is what you see beyond when you know" His story is just a story, it's us the readers that gave it meaning. It almost has to be a story of nothing, so that it has room for our own interpretations to be laid atop of it. In the stories that aren't vague or ambiguous, there just isn't any room in the margins for us to jot down our ruminations on the deeper meanings. The more ink on the page from the author, the less room there is for us to scribble.
Ever since I found out that Hemingway's secret was that the fish was just a fish, I have looked for the places where authors leave room for us to scribble. I had that agnostic mindset going into Godot, so I saw a lot of the space that Beckett had left for me. I think the brilliance of empty stories is how rich we experience them as. A blank page isn't anything to us as readers, but Beckett and Hemingway knew exactly what and how much to write so that each of us can fill in the rest. The way that each of us read an empty story is unique, how you feel about Vladimir and Estragon isn't ever going to be the same as how I feel about them. We fill in the empty parts with bits and pieces from our own stories and our own imaginations and we mix our ink on the page with theirs, it's no surprise stories that stories like Godot and Old Man and the Sea are so close to our hearts.