The point of the parent comment is that they don't fully attempt them. They put forth just enough time and money investment to make a big PR splash and get a proof of concept out the door, then slowly back away from things.
How do you define "immense progress"? Fully attempt to me means actually sinking a significant portion of overall company budget (say, greater than 5%) into a project, marketing it, and attempting to spread it to a wide market. Or put it another way, if a venture-backed startup were pursuing one of these avenues, what would they do? Certainly they wouldn't be content with pilot projects that fizzle out and glacially slow deployment across the country. If Uber were a Google moonshot, they would still be running only black cars in SF.
Google is fantastic at highly-automated software, but really sucks at any kind of real world hardware or service.
Both projects made immense progress over many years -- they just weren't able to justify the costs. IMO, they were actually really good attempts.