Eevee
usually right
Yes, this is true, and I know it is true. That you are even trying this argument on me demonstrates that you really have no idea what the atheist position is at all.But you've never seen one. For all you know, it could all be fake.
1. I do not arrange my life around whether or not giant squids exist. If tomorrow they were demonstrated to be a hoax, that would be a novel addition to the list of stuff I know, but otherwise would not affect me at all. I would certainly not have to restructure my entire view of life, the universe, and everything.
2. There is nothing paranormal or otherwise inexplicable about a giant squid, and thus little reason to suspect a prank. There are also numerous recorded sightings of the creature; a hoax would thus either have to be very wide-spread but kept quiet (which is highly unlikely for the scientific community) or pulled off by someone with tremendous resources without being noticed (also highly unlikely). It is thus far more probable that the giant squid actually exists.
Meanwhile, theists have all the reasons in the world to honestly believe that their pet deities exist, leaving them wide open to all sorts of cognitive biases that trick their brains into seeing Mary on toast or whatever. I am not familiar with any group who is so utterly dependent on believing that a giant squid exists.
But please feel free to explain how the question of the existence of a giant squid is at all comparable to that of a deity.