First of all, this earth is vast. Just look at the area occupied by the Pacific Ocean. It’s fully 30% of our planet. There are going to be several type of creatures lurking in the depths that we have no idea about. If the legend of the Kraken(Giant Squid) is anything to go by, considering that we have not only found it but also found a bigger one, aptly called the Colossal squid, it is no wonder that we could find many more species on land too.
So, is it any wonder that legend of creatures unknown to science are very prevalent. Sometimes they are true too. Just take the case of the lowland Gorilla. Until the middle of the 19th century, we had no idea that such creatures even existed. Now, no one gapes when we talk about them in very familiar terms.
One could argue that in cryptozoology, there is a difference in searching for creatures previously known to science that have gone extinct, the Thylacine for instance, and those that have not been observed or otherwise do not have material remains(Nessie or BigFoot).
The former we can perhaps find existing members, very much like what happened with the ivory-billed woodpecker or the Takahe because they have been documented before. The latter, are very much in the domain of myths or legends because we have obtained either no evidence or very sketchy evidence yet. Does that mean that creatures like the Yeti cannot exist because we have not seen anything of them yet(assuming sightings, footprints and Buddhist artifacts don’t count)?
This gets tricky because we did find a hominid, yes, that’s right, a hominid, as late as 2003 on the island of Flores. Of course, local lore mentioned small human-like creatures living in the forest but they were dismissed as local myths. Perhaps, this is a weak example because the fossils found are only about 20 thousand years old. The homo floresiensis have been extinct for a while now.
So, what about the Vu Quang ox? This is a rather large animal and it stayed hidden from the scientific community for a long while, described in older literature rather derisively as the Asian Unicorn. How do we account for it’s discovery as late as 1994?
It is probably wise not to pass snap judgement on creatures that have been described but not yet found. Who knows if the Mokele-mbembe does lurk in the jungles of Congo? In these matters one is wise to be a skeptic. It could even be so that many sightings in this video are true.