We felt the same way. Movies cut so much out of the books. We also wanted to encourage reading over screen time. If she wanted to watch a movie she had to read a book and she only got one movie a week of screen time m until she was in middle school.

We were more strict when she was younger and have loosened it up a lot. She also was pretty sensitive to scary/suspenseful scenes so knowing what will happen from reading it first helped temper her fearful reaction a little.

At 16 she is a major bookworm and has an incredibly creative mind. For more adult content like Game of Thrones I would absolutely still make her read first. Either way, she loves critiquing movie adaptations now and we have a lot of fun conversations about good and bad scenes, casting, set, what we’d change and how etc.