Since the AU, I've noticed background updaters (not Windows Update) simply run forever in the background without making any progress, and taking up about 13-15% of the CPU each (very uncommon for anything to use that much for long).
This is compounded by the fact that some programs simply won't "open" after being launched, even some installation EXEs. They'll simply sit in the background running forever, but going nowhere.
A good example is the Atom editor (and other Electron-based programs). It's updater will launch multiple processes... that are eating up CPU and doing nothing. Meanwhile it's installer ALSO launches, disappears to the background and just runs as a process forever, going nowhere.
Atom is just an example, there are other programs doing the same thing. Though, it seems background updaters seem to be the most commonly affected.
Almost every article I come across is related to the Anniversary Edition getting stuck, but nothing on my particular oddity.
Running in Win8 compatibility doesn't make any difference as far as I can tell.