this is roughly one possible interpretation of the Fermi paradox. what if other intelligent thinking beings are out there but operate on a very different timescale? what if their speech-cycles are a millisecond, or a millennium, and we're either missing them or mistaking them for static equilibrium
The only reason why people can think a brain is "thinking" is because of the illusion of an instantaneous response. If people performed the same neural state changes over a few centuries using paper & pen, at no point in time would anybody believe there is thinking going on.