It's a joke, you see. If we wait, eventually a star will come close enough that we can just hop on over to it. Thus interstellar travel with no extra technology needed, apart from that which would keep us alive if another star were that close.
Love it. You simply throw a rope around the passing star, and it yanks you right off the planet. For the less-than-alert reader, if you can accelerate to the speed of a passing body... you don't really need that body.