Re: It's not the UI that's the problem
I've rather wondered about that, myself.
The thing is, even with the high activity level, Win 8.1 (and Win 10) can still be used at that time. At the equivalent time with Win 7 I can get very little done, at least on my Asus laptop and on the hand-built desktops which have Win 7 around here.
I have noticed a lot of network traffic being intercepted by my firewall around those times. Why, if I were a suspicious, paranoid, cynical old git I'd almost think that MS has been doing a lot of, ah, 'telemetry', for a very long time. Certainly the Linux machines around here (mostly Fedora just now) don't do anything of the kind. The Macs are, if anything, worse than the Win 7 machines.
Doesn't matter, a good firewall sitting on non-MS (and Apple) hardware is your friend.