Exactly. Even if throngs of people in our future(s) are constantly changing the past on whatever scale you like, we will never ever see any evidence of it. Nor will we ever see it done. Because when it is done, the time line leading up to it being done is destroyed and so it never happens.
If we could sidestep the timeline and see it from the side (a la Flatfland-style), we might see a web of alternities with a plethora of changes being made all the time. But, from our position here in the timeline being effected, we can never notice the results.
Any such changes would be from timelines that we can never experience. They will be, to us, done in the same kind of places as the place electrons go to traverse over to the other side of the atom instantaneously.
From the confines of our timeline, those making the changes cannot and will not ever exist.
w
