I run the server version of Windows 8.1 at work, and have all my apps pinned to the task bar or whatever. Same for when I was running Windows 7 prior; never went to the Start menu (because I've always hated it). I shudder to think if there are very many people that sift thru that hierarchical behemoth of a usability nightmare each time they want to launch an application. Then they'd see live tiles jiggling in their face, but hopefully practically no one is that silly. As you say, I think most people like to customize/optimize their workspace.
Speaking of which, every time we move to a new version of Visual Studio at work (on our 5th now), I waste time fiddling with it getting my child windows arranged and toolbar buttons that I like and the keyboard shortcuts that I like. Some employee productivity will be lost when moving to something new, but only initially.
And as far as social media feeds, people already spasmodically check their phones for that. And they probably don't want their employer knowing how much/often they're farting around with social media while at work. Since nowadays everyone knows your employer monitors your computer activity, I would think people wouldn't even set that up or use it on their work computer. Better on their phones where only the government can see it.
p.s. On a personal note, while your wanting to return to Slashdot is quite mind-boggling, I'm very glad to hear that you're doing okay.