Fascinating. I consider systems like Android, Windoze and MacOS to be like toys for the same reason: superficially beautiful, but not actually a good tool for work.
Suppose you have a document open. You want to attach it to an email you started writing. In MacOS, you drag the icon from the window's title bar into the email. That's it. No need to browse to the same thing you already have on the screen, because your desktop is a set of objects you interact with... Not a window manager.
If you want to open a file browser, you can right click the title bar on any document, and it will give you a breadcrumb of all the parent directories.
If you move a document you have open in an application, the application will notice, and save further changes to that new location too when you go back to it and press cmd-S.
These are just a few little things in one aspect of the OS. But macOS is full of them. Like consistent keyboard shortcuts.
Or multi touch gestures that act while you perform them, not just trigger an action after. There is a commitment to making the computer work like it should, instead of making the human adapt.
Meanwhile in Windows land, even the official apps can't figure out how they want to look or how they want to work. And this is what Linux desktops based themselves on.
There are of course signs that Apple has also lost its magic, and that a new generation raised on touch and web and cloud has no idea how this stuff works. The idea that you can e.g. scroll casually through a decade worth of emails with one flick, offline, is a pipe dream in Gmail land. It boggles my mind that basic conveniences like sortable, resizable and customizable tables are now a luxury in many apps.
But there still is an insane amount of design thought that went into macOS, and everyone else is years behind. That's just a fact.
And two things OSX is absolutely unmatched in: spotlight and preview.
Even if the poster was kidding, it's symptomatic of the Linux ecosystem — never strive for better, what we've had for years is just fine, and be sure to mockingly put down any idea that dares to lift things up.
Mind you, I say that as a macOS user (although I did run Linux full-time for a good six years in a past life), and I'm sure many a Linux user will call the macOS interface toy-like to their eyes.
Even though all I see, whether in the old screenshots are the current, are misaligned and seemingly randomly-sized icons, ugly text rendering, and an unclear design vision, I'll still say that the typical defaults still do a pretty good job considering that no Linux distro with mass appeal has yet shipped with a forced theme to make everything just right because, after all, such a distro would never gain mass appeal to start with.
Not with the Linux users who know they're running Linux, at least. I think this is what Ubuntu and elementaryOS are trying to establish: Linuxes for people who don't know what Linux is. That gives some freedom for forcing good, consistent design — but not until there's enough "first party" software to make the rest of the Linux application ecosystem irrelevant.
I don't think that'll happen until Ubuntu or elementaryOS bring about killer apps, something like iLife for Linux. Beautiful, works exceedingly well, and designed for ordinary people rather than fellow developers. A reason to develop for that one distro rather than the whole Linux ecosystem, so far not yet forthcoming.