Win10 update has almost hung my Wi-Fi over past week, causing big charges on my mobile data over past two monthly bills (+£60). My notebook has been stuffed with bloatware, and systems have been changed (eg date format etc!) Do I have any comeback with MS, as I did not authorise this download, nor was I given any notification. I will also need to apologise to my internet provider for accusing them over poor performance!
Go into your windows settings and set updates to a metered connection. Updates will only go through when you say so, and you will avoid unnecessary overages. You arent going to get anything out of MS because you agreed to their EULA by using their product.
That being said, windows updates arent really large enough, or common enough, to be the only cause of your issues.