Well, I'm certainly not saying it was a bad choice to do that... Everyone has preferences on what they want to do and use. There are plenty of reasons to like OSX.
And yeah, if you just jumped from Windows XP or 7 to 10, without paying much attention... It could be a bit of a culture shock. 10 superficially looks a lot more like 7, but works a lot more like 8 should have.
There were actually some pretty big changes in account management from 7 to 8. Most of these got completely missed because everyone was caught in the "OMG THIS UI IS SO LAME!!1!" outrage. (Which was pretty rightfully deserved. The UI in 8/8.1 is absolutely terrible for desktop/laptop use.)
But Windows 10 works a lot more like a device than the typical desktop OS like XP or even Windows 7 was. There is a lot of benefit to this, and honestly, I expect Apple will go this way soon enough, as well. They've been aiming to unify more and more of the principals between iOS and OSX for years. They're just a bit more politically astute and been doing it slower. Whereas Microsoft just figured it would be a good idea to scream "CANNONBALL!!!!" and dive in, making as big a splash as possible. And they're dealing with the rather predictable backlash, now. Windows 10 requires some rather blunt changes to the mindset you approach the computer with.
But those changes are not anything you shouldn't already be familiar with. You just don't realize it, yet. I mean, when was the last time you thought of iOS as an OS? Probably never, right? It's just the thing that manages your iTunes account and associated services. Windows 10 is obviously a full Windows OS, and carries all the heavyweight background that entails... But it tries to mask a lot of that, and hides it behind all those account management functions. It manages your Live account and services for your personal device, and domain account and services for corporate devices. In a lot of ways, this is really good. It marginalizes the hardware, itself, and makes your computer experience more about your own accounts and data, and less about managing the physical computer. Now, obviously, it's still got a ways to go, but I believe it is a step in the right direction. Even if it's also a bit of a stubbed toe in places.
And, finally, the whole privacy nightmare of "information collection for validation feedback, test data, performance information" stuff is done by absolutely every modern device. Find me a cell phone, router, desktop OS, gaming console, blu-ray player, smart TV, cable box, DVR, or any home automation tool that doesn't do that. I'm not saying I like it. I'm not saying it's right. But that is modern technology. As I see it, you still have the same three choices.
1) You can go all off-grid and harvest your own everything. Live in isolation.
2) You can still try to live a modern life, but force your digital devices into isolation. Sure, it means you can't have a cell phone, as you have no way to monitor its connection... But nothing saying you can't set up a private wired network and have a firewall that blocks everything but the traffic you specifically allow and bless. Of course, you better make sure that your firewall is running open source routing software... And better double check the schematics of the hardware, too... And of course it means you'll miss out on all the updates, fixes, and performance enhancements in trade for not sharing all that other data. Plus it is a giant pain in the ass. And some of those networked features are really nice advancements...
3) You can accept it, and accept the somewhat queasy feeling that you don't know exactly everything your devices do or see. Because even under cases one and two there are a lot of loopholes and things that can still catch you...
But these are the same trade-off options you've already had for years.
In short, I'm not saying Windows 10 is awesome. But so much of the perception about it being so much more invasive than every other product is just that... Perception. Frankly, I trust it more than I trust an Android or iOS device. Take that for what it's worth. (Not much, as it is very obvious how little I trust my phone.)
