Hello,
Thank you for posting in discussions.
First things first concerning the Finder Window for your iOS Devices: When you plug it in for the very first time you need to click trust etc.
Secondly, it will appear as grayed out as long as the Syncing process is concerned - If you can recall on iTunes, there were 4 steps, 2 out of the 4 where the diagnostics and the sync would take place.
Wait for the initial sync to be completed then the Back Up etc Options will become available.
If you are still experiencing the same issue, unplug, restart the iOS Device and plug it in again.
If the same issue persists, let me know.
All the best!
Kind regards,
Andrew
iOS/Mac Product Specialist