I'm not sure who this blog is talking to, it feels like classic straw-man argument. Ford never said the car wouldn't solve anyone's problem, in fact his pitch was that the car was better than a faster horse.
Whatever Ford said, this quote is famous (most likely he did not say that, btw)
I just took that bit at face value, but you are right... and makes this blog post even less palatable.
It's an argument against using the quote to suggest that you don't need to validate ideas against real users.