I liked how it was before. Personally, I find the blue too distracting and it clashes with the near-black / white of the dark and light themes. Only with a blue wallpaper I thought it looked good (this launcher + widgets), but I hardly ever look at my wallpaper.
I think this change would work better if Plasma offered users a way to change or at least tint theme colors.
This is just my opinion, though.