I and it seems many other viewers, disagree. The death of Barry's mom has weighed on him since the show began. Nwhe seems able to move on. That's a significant development for Barry. Now you might find how it happened to be boring or too talky, but to say it didn't move Barry's character forward would be wrong.
I just don't agree. He talked to a fake mother for a bit, and read a stupid book. Its like when Sisko talked to his Mom in prophet form, but at least she was actually kind of his Mom. Barry's stuff with his Fake Mom was just stupid and pointless, like every other speed force scene. He didn't "move on" from anything. If he has moved on from his mother's death death, it was when he traveled back in time but decided not to save her from dying. It wasn't because the Speed Force watched too much Dr. Phil and tried some reality show style "therapy" on Barry.