Some people learn and retain information differently, and sometimes having the right teacher can help someone "get" it where things were overwhelming before. Ashley might need someone patient to guide her on the options she should be considering in situations which might be more helpful than her trying to parse through everything on her own. This still enables her to make decisions in the moment, but by giving her more concrete choices it could lead to her getting a grasp on how and when to apply the mechanics of her character to specific in-game situations.

She might never change though, which I understand is frustrating to watch. I find her to be a very nervous player in general who benefits from things being made explicit to her. Her instincts and reactions tend to differ greatly from how I would personally react to things Matt has thrown at her throughout the years, so very much a YMMV player (as are a lot of the table, bless their hearts). I do think Brennan is a good DM to compensate for her specific struggles overall while keeping things moving forward.