As this deals principaly with archeology and pre-history, this is more a question for r/askanthropology . That said, I would caution against any absolutes when speaking of an artefact of that particular era, as we have so little information with which to analyze and all we can really do is speculate, though some speculations are more reasonable than others. For instance, the suggestion that they are ancient pornography is probably a poor one as it just doesn't line up with the time and skill required to carve them nor their later variations that skew more symbolic and figurative.