Earlier quoted context omitted.
Just double click the top of the window? If I'm understanding right, that's what you want. I only ever double click windows on both Mac and Windows.
Was long time ago I used macOS in any professional capacity, but doesn't it just maximize the height of the window, not the width? I seem to recall some UX like that, but might have been a different action/button.
Seems like the app decides what the behaviour is. But the point being it's the same behaviour as the Option + Maximize.