Sorry, really? You can't even tab between controls in dialog boxes by default on a fresh install without turning on "Use keyboard navigation to move focus between controls", which you ironically can't enable using the keyboard. Seriously, go try it: open System Preferences and try to do _literally anything_ without using the mouse.
Even Finder is wildly unintuitive at times: Enter renames a file, while cmd+O opens it? Or cmd+down, apparently. Press space to show the quick preview of a file, and then cmd+O to open it: the quick preview morphs into the Preview app. But then press cmd+Q, and instead of quitting, it turns back into quick preview.
While I'm a macOS user full time, my experience is completely the opposite of yours. I've constantly had to learn weird nuances of how Apple has managed to make keyboard navigation more complicated than it needs to be.
Even Finder is wildly unintuitive at times: Enter renames a file, while cmd+O opens it? Or cmd+down, apparently. Press space to show the quick preview of a file, and then cmd+O to open it: the quick preview morphs into the Preview app. But then press cmd+Q, and instead of quitting, it turns back into quick preview.
While I'm a macOS user full time, my experience is completely the opposite of yours. I've constantly had to learn weird nuances of how Apple has managed to make keyboard navigation more complicated than it needs to be.