I agree, I think GP is overly cynical. There's a strong chance that the primary reason is for personal utility. But MS (like all big tech) are all about two-birds-one-stone wins. If you can get the personal utility, while also gaining capability that "rightsholders" and advertisers, etc will want, that's a huge win to them. Reminds me a lot of Apple's hardware DRM that is primarily about reducing the value of stolen Apple hardware, but which also serves to make third party repairs way more difficult and expensive, which is not a "con" to them.