Rapid Chess * pmetzger vs vincentraia

English Opening: Anglo-Indian Defense

5 e3 I was very confused by the opening choice, seemed fairly random, so Decided to just play for the center

6…d5 I was not crazy about, but white did not castle so I decided to just play for the center. White blundered the pawn.

8.. Nbd7 hyper aware of threatening light square bishop and white’s ignoring of the center.

12 Bb2 is played, blunders a fork. Why did they not just castle?