Are you aware that you can search the menu from the help area? Or just cmd-shift-?
I can give more examples. The default on Mac, for a very long time, has been to not allow tab to navigate all controls in windows and dialogs (the default is only text boxes and lists). This has to be changed by the user in System Preferences.
Another point on keyboard support is how it's missing on macOS in certain places. An example: Download a DMG file of an app that's already installed (say you're doing a manual upgrade), open it using Cmd+Down Arrow, and then copy the app into /Applications (let's assume the keyboard is used for this entire flow). If your user account is not an administrator, you'd get a dialog to authenticate first, and then another dialog in response to the fact that an app with the same name is already there in /Applications, with options to Keep both versions, Stop the operation or Delete the older version. On macOS Mojave, I find that this dialog cannot be navigated using the keyboard at all (hitting tab or space or Enter does nothing)! The trackpad is the only way to respond to it. I have never seen this kind of behavior on Windows dialogs, whether they're from an application or from the OS (for UAC or other permissions).
Also, if he's not it kind of proves the point of the article.
He suggests that every system has those quirks that you will learn to navigate around.
The vast majority will not learn that ctrl + click does right-click, and that you can enable scrollbars again to actually see if there is more content to view.
How are they suppose to learn that ? Is it described in a help text somewhere ? How about Shift + Click ? Or Caps Lock + Click ? Will this destroy my document ? Now seriously. People (except children) have a lot of other things to do instead of doing detective work.