Probably one of our strongest biases is that our mental models reflect the environment in an objective manner that depends more upon the nature of the environment than ourselves. More likely, our mental models reveal the nature of our cognitive abilities in the context of the environment which expands beyond them.
My dog cannot fathom my tax return. That reveals more about his cognitive abilities than it does the nature of my tax return.

This actually might be harder to grok for typically intelligent people because they don’t have much experience with encountering mental models they cannot hold.