All the final bosses were brought up to match the boss with the best loot package. We didn't nerf any of the existing ones.From the notes:
"The loot for all Shadowguard bosses has been normalized so that loot is standard regardless of which of the Shadowguard bosses is encountered last."
This makes me a little sad. While it was a pain in the butt to have to enter and exit the Roof encounter until getting either Virtuebane or Juo'nar last, I am really hoping this didn't end up with a massive loot nerf...