I used to be a true Ayu-fangirl years ago, there was not a single song I didn't dislike from her.
But now I'm more critic. I hear her songs also with brain. I dislke just 3 songs from her, some are meh, many others are wow and few are AMAZING YOU'RE THE TRUE QUEEN OF JPOP
. I think it's normal for a fan, there's nothing wrong.
Lately her music has more ups and downs than before, but I don't think the music quality it's so highly decreased. She's playing safely due to low sales (I mean compared to her old works, her sales are still pretty good these days though) and for keep her streak and fanbase. So she experiment less than in the past, but she's still experiment.
Most of people here have too high expectations, I think. Keep complaining because her music sucks after Memorial Address, MY STORY, (miss)understood and go on. Just let down your expectations, just a little. And enjoy her music as you can, not for compare old to new.