That would be true if the GUI worked correctly.
The GUI works correctly for the vast majority of the time.
And MacOS and Windows also have GUI bugs, but we are so used to using these OSes that we know the workarounds.
The difference with Linux is that depending on your desktop environment, you will have to learn a new workflow. On Windows and MacOS, you one desktop environment and that's it.
However, more often than not, some inner thing breaks, which means that the GUI just throws an error screen and tells you "good luck". So you have to search for that text in Google, and it will send you to an obscure forum where a guy said in 2014 that the solution for that problem is to run some random command in the terminal.
Happens with Windows too where you get an error code and then you have to registry entries to fix a bug. Again, same kind of issues with a different workflow.
For example the "app store" GUI for Kubuntu never worked for me. It always stalls at some point or another. Meanwhile, running sudo apt upgrade worked flawlessly. Both operations should be doing the exact same thing under the hood
I've had lots of issues with Windows store where a software wouldn't install correctly and I had no way to install what I needed to. At least, with Linux, you have multiple way to install a software. The app store is just a GUI over the package manager.
Two times already, a relative that uses Manjaro but has no idea about Linux came to me for help because the "app store GUI" (which is a different one than in KDE) one day stopped working. The issue was to run some random key-relayed command.
I do the IT for work (small company, 4 employees) and the number of time I had to un-break something in Windows for no apparent reason is high. Bugs happen in any OS. Linux is no different.
Years later, I found out that apparently the Manjaro maintainers let their certificates expire MORE THAN ONCE. Which has to be fixed manually by the end user apparently. And they apparently didn't think of adding a notification in the GUI telling you about this. Which is bonkers. Not everyone reads all the news articles relating to their OS.
That's dumb and I agree with you, but that's not a Linux issue though, that's a Manjaro maintainers issue.