Since I am not a software engineer, an electronics engineer, nor a "computer hobbyist", my thoughts on Windows OSes are from the perspective of a computer user. I simply view a computer as a tool that can help me perform certain activities.
The activities that I want the computer to assist me in are: 1) collecting information (i.e. web browsing), 2) storing information (e.g. accumulating data into a database or capturing my thoughts on a subject in a word document), 3) sorting information (e.g. manually storing documents into a hierarchical filing system or querying a database), 4) manipulating data (e.g. using a spreadsheet to perform calculations, using a mechanical design program to develop a 3D model of a a part, or using an image processing program to change the contrast of a photograph), and 5) to share the results of these previous activities with others (e.g. sending an email, sharing a file, or posting a YouTube video.
With the above "wish list" in mind, I would have to say that all the windows operating systems of the last two decades are successful in varying degrees. But, it seems to me that they are getting progressively worse in some aspects.
My main complaint is that when I buy a tool, albeit a computer or a hammer, I expect to have a clear understanding of what that tool can do for me, a clear understanding of how to use that tool, and I expect the tool to save me time/effort/money.
With a simple tool like a hammer, it's purpose and how to use it are fairly intuitive, so the manufacturer doesn't really have to provide documentation outlining its benefits or usage instructions (although they may advertise how their product is superior in balance, grip comfort, etc. and most will have a safety warning about the risk of shattering the head if used to hit another hammer, but, I digress). Determining the cost/benefit of the hammer is left to the buyer, but, there is a generally accepted understanding that the hammer is unlikely to require any periodic maintenance and that it will last for decades.
On the other hand, computers and the software used to operate them are extremely complex. Just by looking at a computer or its operating system, a buyer can't tell exactly what it will do, how fast/well it will perform, how much maintenance it will require, nor how long it will last. This makes it nearly impossible for a non-IT buyer to access the cost/benefit of a computer or OS. If they are really motivated to understanding the tools, they have to either go to school to become an IT professional or spend countless hours reading blogs & websites and watching YouTube videos. But, if they choose to do so, they need to factor all that effort into their cost/benefit analysis and they will most likely decide that it's in their best interest to just buy a PC that comes preset with an OS and a suite of commonly used software. And, if it stops working it's best to either have an IT professional fix it or just throw it away and get a new one. I would liken this to buying a Crescent wrench instead of buying sets of metric and SAE combination wrenches, gear wrenches, and 1/4", 3/8", and 1/2" drive ratchet wrenches and sockets. If you only occasionally need to tighten a bolt, the Crescent wrench is fine, but, if you are a full time mechanic, you'll want the whole assortment of wrenches because, in the long run, they will pay for themselves.
Getting back to Windows 10, I would have to say that, on one hand, it is amazing all the things that it can do, but, on the other hand, it is appalling that the buyer doesn't really have a clue exactly how it does what it does. In the old days of "sneaker net", I knew exactly what information I was sharing and with whom I was sharing that information because I'd copy a file (e.g. a Word document) onto a floppy disk, carry it to a co-worker's desk, and give it to them. These days, I have no idea what information my computer is exchanging over the web, where it is going, where it is being stored, who has access to that data, or what they are doing with it. Personally, I wish all OSes were designed such that all data going out to the web had to be user approved and all incoming data had to be in response to a user request (e.g. go to this web page or download this file).
As to the quality of Windows 10 (and all it's recent predecessors), I'd have to say it is a PIG (no disrespect intended to pigs!). With all the legacy crap it carries, I'd liken it to buying a new Corvette and finding out that GM had evolved the car since the 50's without deleting any obsolete hardware - it would have fuel injection, but also a carburetor, electronic ignition, but also a points distributor, bluetooth audio system, but also an 8-track tape deck, etc., etc..
For the past week, I've been struggling to do a fresh install of Win 10 on one of my laptops. I started with a simple install to a cleaned and reformatted HDD from an .iso file I downloaded from the MS website to a USB stick. I just installed per all the MS defaults and all went well. But, I was not happy with the disk partitioning because of the way file explorer displays things. I want a partition for the OS, a separate partition for programs that I install, and a partition for my files (Word docs, Excel spreadsheets, music, photos, PowerPoint files, MS Project files, etc.). I want to store these types of files in a directory tree of my own design. I most certainly DO NOT want to store my files in my user folder. When I open file explorer, I want to see a drive (partition) that, when opened, only shows the folder tree that I have developed. I DO NOT want to see links, favorites, downloads, desktop, etc.. I also don't want to see "Quick Access", "Libraries", "Frequent Folders", or "This PC". When I open file explorer, all I want to see is C:, D:, etc. and I'd like to be able to hide any drives that contain system files (e.g. if Windows OS is on partition C:, I want it to not display in file explorer).
I also want to be able to open multiple instances of file explorer so that I can more easily drag and drop files from one open folder to another. This used to be possible, but, by default, it seems that Win 10 won't open multiple instances of file explorer unless Win 10 opens the second instance on its own (e.g. if you plug in an external drive) - I'll have to Google and see if there is a workaround for this. Suffice it to say that file explorer in Win 10 is an abomination that does a horrible job of helping the user locate a file. It is almost easier to navigate thru directories from the DOS command line.
Another serious flaw in Win 10 is that it still has various system control/preference settings scattered all over the place (Settings, Control Panel, Computer Management, Task Manager, System Information, System Configuration, etc., plus all their sub menus). Even God Mode doesn't provide access to all the various settings.
All in all, for those who are not at all computer saavy, Win 10 is like a Crescent wrench, for the very tech savvy, they can probably navigate their way through the Win 10 setup and preference options to make it work the way they want, but, for those of us who aren't very computer tech savvy, but know exactly what we want the computer to do, we're in for headaches because Win 10 is quite a Byzantine maze!