i have to agree with you, and i suppose in doing so dismiss the the ability that any such space faring race hasn't discovered yet how to travel much faster than the speed of light, or fold space.
i wonder why guys like this would say they saw what they did. were they confused.
will we know advanced space travel (faster than light speed, space folding, worm holes or something else) if so when. if it will be between 100 and a billion years then we have to assume that there is probably a lot of races who are a billion years older than ours with similar styles of travel.
on the other hand if space travel is only limited to less than light speed we may never see another race on earth, ever.