I don't know how many people still use Disk Cleanup this very days.
But to keep my sad 120GB SSD on my surface feels better, since I always put too much stuffs in it, so I do use it.
And unfortunately I got this issue.
Whenever I use Disk Cleanup right after I completed update my Win10,
it gets very very slow down at step:Windows Update Cleanup.
It will take about 1 and half hours to finish.
I tried cancel it, but that will make the next computer Restart takes that long too, sometimes fail startup even.
I guess we may already get those needless update files deleted automatically by Windows Updater, right after they were installed.
But that confused Cleanup and make it slows down.
So that's my guess, just some user's guesses of someone knows nothing about programming.
I literally don't know how many users still use this old function.
But I think making the whole OS works coordinately and appropriately is kind of important, right?
Just wish reporting this problem will making the OS we're using gets better.