it's utterly ridiculous and totally irresponsible to dish out a 10 GB update.
Indeed!
About the reason(s), sorry but so-called security is just a bait. It smells more like some AI **** inserted into the app and, like I already said, a bunch of spywares and logical valves to remotely lock up some functionalities on demand.
Whatever is proposed, it's up to M$ to solve the issue they created post-contract, not to the customer.