Well, of course all this could be spot on. Or it could be complete bunkum. It's speculation, which is fine, but when it involves stuff like "for over 70,000 years, people came to this cave for the sole purpose of performing rituals, and nothing else" it claims to be more than speculation, and the claims go way beyond the evidence, as Topsie pointed out.

Just think of all the weird and varied stuff we get up to in the course of our lives, and then imagine a claim like that being made about some aspect of our own life by some imaginative paleontologist a few thousand year in the future, on that kind of evidence.