We see reality as it is captured by our input sensors, and processed by our vision system. That signal chain is where the subjectivity comes into play, as well

We see reality as it is captured by our input sensors, and processed by our vision system. That signal chain is where the subjectivity comes into play, as well as the edge cases where our vision systems misidentify something, or see something that isn't actually happening. It also defines what our reality is, based on the capabilities of the sensors. The existence of optical illusions prove that we don't see reality "as it is", or those illusions would not exist, and we'd just see what was there. The existence of both color-blind people, and tetrachromats, also prove that we don't see reality "as it is". Look at any of the other species in the world with differing vision systems to understand that at most we see what reality is for humans. The really wild part of all of it is the way our brains can perceive things out of order, in a sense. The way our brains fill in microsaccades is wonderfully interesting. It's why the first tick of a second hand sometimes seems like it lingers.