Anyone who wanted the CLI has had plenty of choices of various operating systems and distributions over the years. Ubuntu's strength is that it's useable and installable with a minimum amount of CLI. That means there's less of a barrier to newbies and casual users.
("Real" users can use blinking LEDs and chorded keyboards instead of fancy GUI cheats...)
Though I agree that they were less innovative than I would have liked on the graphical side of things. However when they did 'innovate' with Unity people complained (and still do). Not a lot, but they were extremely vocal.
That's not to say that CLIs aren't powerful - I have a terminal open all the time, and for many things it's the quickest option. But I think we underestimate how useful GUIs can be.