I suspect it's a function of your use cases. I've used Linux on the desktop since the late 90s, and I still use it every day. My employer makes me use MacOS for work, and it's a constant source of frustration for me, but Linux is consistently wonderful.
Vague criticism is useless though. My frustration with MacOS is mostly that stuff is either broken or unintuitive. I use Emacs, and after upgrading to Catalina, Emacs could no longer open files on my Downloads folder, even after manually assigning it permissions to read the entire disk. This turns out to be because Emacs has a Ruby script it gets launched through that has distinct permissions from the executable itself, so I have to hand-tune the launch scripts to make reading from disk work correctly.
There's lots of stuff like this. Mouse avoidance mode on Emacs is broken when it is set to 'banish, completely breaking the ability to drag the Emacs window around the desktop. Took me a few weeks to track down.
I want to tile a window to the side, so I have to click and hold on the full screen button, then select a side, at which point MacOS goes into some weird full screen mode and forces me to select some other window for the other sid, which I didn't want. I just wanted to tile a window on one side. If this feature were launched in Linux, I fear the derision would never end. Pop!_OS did it better.
For some reason, MacOS can't remember that I type Dvorak. After I log in, it remembers, but on the log in screen, I have to manually select Dvorak every time so I can type my password. If I've already selected my account, there's no reason it can't do that for me. Linux does, except Elementary OS, which is broken in dozens of other ways as well.
If I touch the play/pause button on my headphones by accident, my entire desktop gets buried beneath iTunes (I guess Apple Music now). I had to remove execute permission to avoid this, but updates seem to revert the behavior from time to time.
And this is just me trying to run Slack, Emacs and a browser. I'm not even doing anything fancy. So when I hear that Linux isn't ready for the desktop, it just doesn't resonate with me. I've used it for decades as my daily driver, and I plan to continue.