I happened to watch a snippet of video in a similar vein a few days ago. Not with dinosaurs, but with the homo genus. It was explicitly framed as wild speculation rather than any kind of theory because there's no evidence for it, but even over that much shorter period of time evidence could be extremely scarce or no longer exist at all.
I've seen this kind of thing stated several times in this thread but I think it's actually quite unlikely. That's based on the findings on potential burrows for basal ceratopsians, dinosaur footprints, the entire catalogue of trace fossils going waaaaaaaay back and even the stomach contents of Borealopelta. If very early humans had developed some "higher tech" then we'd probably find something. Although perhaps we just haven't found that T. rex keyboard just yet. It's a cool idea though.