The web/webapps/mobile helped lead to this era of "desktop PCs" (to include laptops) where the browser mattered more than the OS. It allowed Apple to become resurgent in the desktop market because OS compatibility mattered less than ever. It's not weird that it led to Apple regaining _some_ market share because clearly there was demand for the Apple/MacOS/OS X experience that may have been tempered by incompatibility…
As an Apple Stan, I don’t understand what you’re referring to. MacOS is light years ahead of Windows in so many arenas, I’m not really sure what you could be referring to when you say “stagnation”. Every OS ever released has issues at launch, not sure if that’s what you mean by “regression”. But man… windows has been garbage for the better part of 2 decades now.
Someone else on HN has a line that I agree with:”Apple makes the OS apps mundane so that people can write replacements and sell those in App Store where Apple has a fat share”.