I tried to address the issue of Canadian Tech supporting his current 150 client computers, which i assume will only grow, and offered a suggestion on how he could maintain his clients at win7 (a Spiceworks community may better help). Fighting KB3035583 in this thread, seems like a 'pop a mole' game.
It can be ignored, and updates can be controlled.
The choice of most of my clients is still Windows, and Win10 has been a much easier transition than win8, for clients that want(ed) to upgrade from previous OS, or bought new computers with the 'latest and greatest(?)'.
Quickly developing/deploying a new operating system across multiple hardware platforms and infrastructures via an upgrade, required a lot of software/technical feedback, and getting users clicking on an 'agree'; was a daunting task for Microsoft.
But I agree with many 'there are potentials for significant privacy concerns with data collection' from any program or operating system, especially Microsoft Win10. Apple, Google and Linux are not immune from questionable data collection or security flaws.
"whether the benefits exceed the costs as the users perceive them" is an extremely broad question. But the answer has a timeline.
The cost are varied, and AT&T has changed their direction:
More current operating systems have less known security flaws.