itch.io

There are books on what is a game and what is not, but I think that the book that got the deeper meaning is: The Art of Game Design: A Book of Lenses.

In the book, the author define game as “a game is a problem solving activity, approached with a playful attitude”.

What you missed is the "problem solving activity".

The most similar game to yours that I can think of would be Viridi, but there you need to water your plants once a day and plant seeds: even those very small activities create a problem to solve that engage the player more deeeply.