Of course it doesn't prove anything, but simply reminds that YMMV.
Updates are always breaking something, to the point I had to convince her to update to (High) Sierra, so I could install new Xcode, because she didn't want to.
Font rendering is ugly, too bold, I can't look at it. Touchpad is somewhat acceptable - I've used both better and worse. Spaces aren't really useful. But those of course are up to personal taste.
I had some contact with OS X somewhere around Tiger and Yosemite. I had some contact with iOS somewhere around 7.0. I do remember them as quite stable and problem-free, although not really the most usable nor exciting for me personally. Recently I started to have contact with newest macOS and newest iOS, and damn, it feels like every mention of "not having to deal with headaches" regarding those OSes is as poor joke. There are so many of small glitches and annoyances, bugs and poor UX decisions, that I really feel like my Arch is more polished, and that's something. Not even speaking about phones.
Oh man, how? Virtual desktops where alt+tab doesn't cycle through windows only on the current desktop are completely broken (they're just a large virtual screen), and last I used Spaces there was no option to change this.
As far as your point goes: it depends on if you see your Spaces as isolated desktops, or just 'more desktop space' which you can then loosely thematically organise. I fall into the latter category, and I suspect as Apple has chosen that cmd-tab style because most people do.
If you just want more desktop space, why not alt-tab between programs? They're all going to show on the same screen, anyway. Even disregarding all this, the fact that Apple didn't even give me the simple option of hiding programs on other spaces from alt-tab was one of the main reasons that made me switch to Linux.
As far as Apple not giving you the simple switch.. that’s just how Apple is. Again, I like it, because it means any Mac or iPhone I pick up I can instantly work on.. with Linux, the shortcuts differ even between Ubuntu and Fedora! That unified ‘foundation’ gives developers a solid base they can bolt stuff onto. For example, Spectacle. Its a sort-of window manager that would never work if it had to keep dozens of key configurations in mind.
On a sidenote, you needn't have switch to Linux. Command-Tab-Plus[1] has the feature you want ('Isolate applications in Spaces').
Thanks for the command-tab-plus shoutout, I later found Witch (IIRC) that did the same, but it was a bunch of annoyances that drove me to switch (no "Cut" in the Finder, homebrew didn't exist, the Spaces thing, etc). I do miss Photoshop and Lightroom, but I have a second Windows partition I use for those.
For the last two years I've found Ubuntu Studio a superlative OS to be running on both MacBooks and generic PC workstation/laptop hardware, and I've found the condition and quality - and overall user experience - of both MacOS and Windows to have gone rapidly downhill by comparison.
So, I dunno. You say tomato, I say Ubuntu is awesome.
And this is in turn is seriously un-true.
* With my Macbook, I can be almost ironclad certain that if I close the lid to sleep, it will wake up. With Ubuntu (or any Linux really) you have 99,5% certainty, which is great, until it isn't and you lose work.
* Battery life if still miles behind macOS+Macbook levels unless you compromise somewhere (resolution, portability, etc.)
* Apple is quite a heavy-handed overlord that pushes changes through, and developers have to adapt or die to them. Ubuntu has no such power.
* Most macOS developers also 'naturally' stick to platform conventions, so all applications feel at home and look and work as expected
* The ease-of-use of Apple's 'global menu' cannot be overstated. It may not matter much to techies, but for my mother or grandma the fact that 'Print' is always under 'File' and 'File' is in the menu bar regardless of which application is being used is magic. Same goes for 'Edit', 'View', etc. They never have to hunt for these things again[1]
That's not to mention Touchpad gestures, Spaces (best implementation of virtual desktops), scaling, font rendering, updates that rarely if ever bork everything, ecosystem integration with your phone and tablet (Continuity, shared copy-paste and remotely-triggered tethering are a godsend), etc. etc.
Now if you were touting that Linux is much easier to tweak exactly to your liking, I'd heartily agree. But even today, I'd much rather recommend someone a Macbook than have them deal with the headache that Linux desktop _can_ be.
[1] Yes I know Ubuntu had a global menu. They nixed it, and the Gnome extension is a hack that doesn't work for everything