Some people seem to spend their lives doing the dumbest things. They may look at birds all day, identifying and classifying them, and then going home and reading journals about other people who watched birds. Other people may spend all day reading and reading, soaking up knowledge from countless walks of life, but doing nothing with that knowledge.
It is frustrating to see people following trivial pursuits. But what is truly difficult is getting out of your head and seeing that no pursuit is trivial if it makes you happy.
As a writer, challenge yourself to make those activities interesting. If somebody wants to learn all about Egyptian mythology, how do you make it interesting? How do you make the audience care about seeing a main character learn about a subject that "doesn't matter"? If you can answer that question, then you can write about anything.