IMO Windows phone design and Windows 8 Metro were too minimalistic and squared like this, but TBH the current version of Windows has nice design and you can customize the theme and other things.

The issue with Windows now is the unjustified delays and bugs. I think professional PCs suffer the most from bugs because my own PC works fine. Not sure it's completely Microsoft's fault, could be the company. Sometimes the problem can also be the hardware and it's also not completely MS at fault since many manufacturers can produce PC and at widely varying prices.

Not at all, one of the key features of that design system was that the boxes had no borders, and they were differentiated by their flat background fill color instead. There's borders galore here.

Would be surprised, looks nothing like it. Certainly not to my eyes anyways.