The operative word was "hadn't." There's no manner of speaking involved.In a manner of speaking, since Ben's Theme ended up being used generally and pervasively as the Force Theme, Kenobi doesn't have a personal theme, even if one was written for him (and even in the extracts you quote, Williams acknowledges that it was more of a general Jedi theme even at the very beginning). The same thing happened to Luke, who really doesn't have a personal theme anymore, since it had been the main Star Wars theme, but that music has been used for decades in Star Wars stuff where Luke isn't involved.
That said, I agree that in terms of how the franchise has evolved since the original film, both Luke's and Ben's themes are no longer personal or specific.