Have you seen the most recent tablet sales numbers? A German Stuka couldn't dive faster. The only platform holding steady and showing some growth is Windows.
Perhaps you need to improve your comprehension skills. I didn't single out tablets, I said "outside the desktop/laptop market ", which includes tablets, 2-in-1s and convertibles. Those latter devices have keyboards and track-pads, just like a laptop, and those are the devices that OEMs seem to be investing in currently. More importantly, they are devices that rely on a consistently good experience, no matter how they are being used. They need to function as well with or without a keyboard and mouse and this is where W10 cannot hope to deliver in it's current form. Seriously, spend a few minutes turning tablet mode on and off and see just how little it alters the experience. It is a joke.
Please consider for a moment that there are those in many parts of the world that can only afford 1 device. If that 1 device only has a touch interface it may not be for them. Windows tablets are popular because they have mouse & keyboard capability, not to mention run real desktop programs.
I'm not quite sure what this has to do with anything I said, as it holds true for me as much as anyone else. But, as I said, that's where W10 lets me down the most. I am still running Windows 8 on my 8" Thinkpad 8 and it is as easy to use without a keyboard and mouse as it is with one. I bought a 10" Yoga 2 to experiment with W10 (and just realised that I have W10 on a 10" tablet and W8 on an 8" tablet, which is amusing) and the differences could not be more stark. The Yoga 2 is kind of useful with its bundled keyboard and my Bluetooth mouse, within the constraints that it is running beta software, but it is a pile of garbage without them.
I'll give you an example that I think is particularly relevant - browsing the internet - which is something every tablet user would do on a daily basis. On my W8 tablet I use the Metro version of IE11 and the experience is brilliant. All the controls are nice and big, they are easy to get at and I never have to press multiple times to get it to do things, despite the small screen. Best of all, it displays the content full screen with an absolute minimum of wasted space, which means I can actually see more of a web page on my 8" tablet than I can on my 10" tablet because Edge takes up a fat strip at the top of the screen and pushes all the web content down.
I say "fat strip" but the reality I that it isn't fat enough. Closing a tab requires anything between 4 and 10 attempts and opening a new, empty tab often requires twice that effort, simply because the touch targets are way too small. That would be eminently forgivable if Edge was replacing IE on the desktop but it isn't, it is meant to be touch-friendly.
It is easy to think that hiding the UI away is a bad idea but for tiny screens it takes away the compromise inherent in wanting to make it easy to use with fat fingers but still leaving enough room to display your content, whether it is a photo, video, web page or maybe just an email or PDF document. Windows 8 and Windows Phone do that much better than iOS or Android, Windows 10 does it much worse.