>>941480515
This is a contrivance. While it's true many experiences are subjective, the human organism functions on a set of biological processes that have the same function related to conscious thoughts.
If you're going to use pain as an example, another example that makes equal sense to entertain would be nerve disruption. An ant, even though it lacks a dermis, kidneys, a liver or a circulatory system as we know it, experiences the same paralysis as a human when exposed to a nerve agent. This is because nerve agents disrupt the electrochemical processes responsible for nerve conduction. Pain is just another condition of the nervous system. You can argue that the individual's conscious mind can filter some of that pain, but the subconscious mind and passive components of the brain like the cerebellum or motor system will react to pain the same way not just across individuals but across all feeling life.

An even more interesting example are consciousness suppressing agents like chloroform. Chloroform does not act on the electrochemistry of neurons, nor on specific areas of the brain that control sleep. It works by interrupting the atomic and quantum processes necessary for electron transmission within the body.
If the most extreme experience is being unconscious, we have discernable evidence that all life as we know it experiences loss of consciousness the exact same way. This is only proof that most life has sensory perceptions that are virtually identical regardless of brain size or experience.