Too Old for Rider?

Z loved the Alex Rider books by Anthony Horowitz, so I just knew he was sitting around waiting to read the next installments. When I took the picture above at NCTE, I took it because I was hoping it would stir up fond memories of the series and get him reading it again.
Our short chat made me see that I was wrong.
K: When did you read the Alex Rider books (e.g., Stormbreaker and Point Blank)?
Z: 6th grade.
K: How many did you read?
Z: 4

K: What did you like about them?
Z: They were cool. Suspenseful. I liked that they were spies.
K: Who was a spy?
Z: The main character.
K: Are you going to read the new ones, Evil Star (2009) or Crocodile Tears (2009)?
Z: No.
K: Why not?
Z: I’ve outgrown them.
K: You have?
Z: Yeah, they became too predictable.
K: Oh.