Maybe. But so is the amount of time which separates the two. Less than 300 years. If instead I had compared what was man's understanding of nature two thousand years ago to that of today what do we find? Would you still describe the difference as being "small"?
But that's kind of the point mmoore and I are making here at the end. Saying that cave people knew squat, and we know a lot more, therefore we are going to know as much more in another thousand years is syllogistic. One doesn't follow the other. The very fact that we know millions of times more about the nature of nature could be proof that we are getting close. The well is not bottomless. It does have an end. We don't know where it ends, but it could end in another 20 years, at least in terms of having an understanding of any fundmamental aspects of nature that are remotely within our grasp to manipulate. Things to know about nature probably will follow an asymptotic curve, and the further you go along that curve, the shallower the slope gets (statistically of course, there can be discontinuities.)
If we discover that there are in fact an infinite number of alternate universes, to which we cannot go, that will be really cool and interesting, but will have no practical effect on our abilities. We are in this one, and the laws of physics of this one are the ones we have to deal with it.
Of, if we discover that in fact string theory is correct and that we live in a 10 dimensional world, but the other 6 are rolled up in infinitesimally small areas that we either cannot every explore, or cannot do anything useful with even if we do, then that will be very cool, but it won't change a thing in terms of giving us super-human abilities.
So there may be many more things yet to learn, but it many well be that many of those things (such as what the conditions were 10x-43 seconds after the big bang), are cool but there's no way we can use that information to do much in practical terms.
Technology of course will continue to explode (as long as it doesn't explode us first), and 1000 years from now might be indistinguishable from magic to us. To me, that is likely to be more important to us in the long run that time travel would be. Time travel would be a very dangerous tool, far more so than nuclear weapons, and could never really be used without huge risk. So even if it existed, in what way would it make your life better than having a 5000x5000 flat walls screen with 64 bit color and 500Hz refresh rate, playing from a 1 cm square cube? I'll take the wall screen myself, because its great fun and probably won't cause the self destruction of our civilization.