It Was Not an Accident
It is quite obvious to me that there are two factions at Microsoft that are fighting with one another. One faction is wanting to clamp down and control everything right away (users be damned). The other faction, while not necessarily opposed to total control, would at least like to see it done in a more gradual, phased way.
I do not for one minute believe that the reset of Privacy Settings was accidental. As we may recall, not too long ago Microsoft upgraded many Windows 7 and 8 computers to Windows 10 without user consent. They later claimed that this was "accidental". It does not seemed far-fetched to believe that someone at Microsoft simply jumped the gun, so to speak and pushed out the mandatory update to Windows 10. Perhaps this was just to see what kind of reaction there would be. Faced with overwhelming criticism and condemnation, even from journalists with a otherwise pro-Microsoft bent, they relented, and said this was just an "accident", much like they are doing now in claiming that the privacy settings change was also an accident.
I am confident that they will have a lot more "accidents" like this in the future. What unnerves me most is that they have the demonstrated ability to change privacy settings or to force users of prior versions of Windows to upgrade to 10 in the first place.