THAT IS THE POINT THAT IS THE POINT THAT IS LITERALLY THE POINT.
I think a lot of people leaving comments like these are missing a very important piece of context on why this graph was probably made:
Bigfoot truthers VERY often bring up the giant squid and the colossal squid as part of their arguments for how it's totally possible for bigfoot to be real despite the lack of evidence. They will bring up how giant squids and colossal squids were considered legends for a long time, evidence for their existence was sparse, and there weren't any photos of a living giant squid until 2004 nor any footage until 2012 (and there has never been any footage of a colossal squid yet), but science acknowledges them as real animals that exist.
Basically they will bring up the existence of the giant squid as evidence that it's possible for there to be little to no footage of a real animal that exists because the animal just happens to be really elusive and hard to photograph, and then they will argue that it's a similar situation with bigfoot.
The person who made the graph was probably trying to mock this idea by pointing out that if this were the case, the amount of bigfoot footage would have increased over time as cameras become more ubiquitous, just as it happened with the giant squid.
