It is a bit annoying. Arthur C Clark suggested using nano tubes in a space elevator over 20 years ago - so what exactly did google x bring to the discussion?
The fact that they came to the same conclusion (infeasibility) we now question their intentions/motivations and whether it was a good idea or not.
We either applaud attempts or we don't - but we can't choose based on the outcome of those attempts.
If they were even remotely serious, they'd be continuing work and research on everything else relating to building a functioning space elevator and waiting for materials science to catch up, or better yet directly contributing to the advancement of the materials.
Edit: I'm not criticising Google for looking at space elevators. Hell I do applaud that, and I think it'd be a great direction for them to explore. What I'm upset about is Fast Company's journalistic standards about covering it. Google X mentions they looked at space elevators and Fast Company would have you believe they threw millions of dollars and man-hours at it and actually tried to design one.
Journalists apparently have no idea how to cover scientific topics. If someone reports they've found a chemical that's shown to target and destroy a specific strain of cancer cells in a petri dish under laboratory conditions then Fast Company would be reporting that they've cured cancer.
To its credit you get self driving cars out of this sort of strategy, and you also get less PR worthy work :-)