#3: sure, in general terms. Not true in my opinion for the best programmer of the world. Naturally he is "the one" that can master programming so well that it must be able to drive even programming language designers into more expressive / productive languages. djb can never be the one as in his code is very rare to find high level abstractions.
as for #4 it's very admirable to write real world software, but the best programmers in the world, like Joy or RMS tend to write big systems that can be used by the other hackers in the world, because to write a new operating system, a C compiler that live for decades contributing even to the development of new operating systems (It's hard to imagine Linux without GCC in some way), or world class text editors (vi, emacs) is not something everybody can do, but only the best programmers in the world.
Writing a text editor is a relatively easy task and it's more a matter of user interface than of implementation.
Besides, I don't see why writing a mailer daemon is less important than, say, a text editor.
To write a text editor today is very different that inventing the first VIsual editor that is a major step forward, or Emacs that was a similar impressive step forward at the time.
as for #4 it's very admirable to write real world software, but the best programmers in the world, like Joy or RMS tend to write big systems that can be used by the other hackers in the world, because to write a new operating system, a C compiler that live for decades contributing even to the development of new operating systems (It's hard to imagine Linux without GCC in some way), or world class text editors (vi, emacs) is not something everybody can do, but only the best programmers in the world.