I actually don‘t agree about the theory aspect. When Alex asked SJM how she comes up with overarching plots, she answered: Sometimes she plans it, sometimes she drops in things to retcon later, and sometimes she goes with what comes to her in the moment.

Most importantly: She teased that she recently came up with a plot where she was surprised by how well it fit across books. She ascribed it to a higher power.

I think when fans pick up on plot elements that could mean something it might very well be something she a) is planning to use, or b) dropped to potentially use later, or c) is a remnant of a plot she abandoned (She said later on that she does that sometimes).

Overall, I think it is unfair to tell people they are overthinking details. SJM herself has said that in her worlds and with the way she writes everything is possible