Adobe is not deleting stuff like this. There are multiple threads here and on the Premiere forums that have been around since CC 2014.1 first introduced the blue color and they're still going strong.
Also, YOU have access to CS6 still (as well as CC if you would like some of the new features without the blue): How to Find and Install Previous Version of Adobe Apps in CC 2015 | Adobe Customer Care Team
You can install CC 2015, CC 2014, CC, or CS6 from the cloud.
Speaking of CC 2015, there are some additional enhancements to the user interface customizations in that version. It won't help you make it orange again, but it can make it more readable if you're struggling with that. If you do decide to update to CC 2015, make sure you don't let it uninstall your older versions: keeping previous versions installed when installing CC 2015 applications | After Effects region of interest
Okay, why this post has been deleted:
After Effects 13.1 (2014.1) Update changes selected Keyframe Colors - Please revert back!
I see error message. I did not get any notification, maybe I was banned in this thread, but who knows, it just stopped to open, for me it was deleted thread.
That's odd. Perhaps the original poster deleted the thread or something. There are several other threads that are still around regarding the subject, so I wouldn't start believing in any thread-clearing conspiracy just yet.
Okay, I hope it was just one occasional case, I hope someone can upload this folder with pngs and everyone who want to revert old design can replace icons.
I don't want to install old version just to copy this folder, if I would know new CC design such ugly, I would backup this folder, but unfortunatelly I did not know
Some one please help with!
I missed out on the keyframe-color altering pngs with instructions too. I bookmarked that discussion to read through when I got home, but by the time I got home the thread had been deleted.