Reality can be boiled down to a simple equation: perception + experience. What we receive via our senses is interpreted by the knowledge we have gained by our experiences, and this outcome is what we call reality.
If, for example, I existed during the era of the Roman Empire, I would perceive the sun arcing across the sky, and the experiences of my upbringing would inform me that it was Apollo in his chariot. If I had never experienced anything to tell me differently, then that is how I would view reality. It’s not that I’m dumb or wrong, it’s that my reality is shaped by the things I have learned and by the things that I see (touch, taste, etc.) I wouldn’t believe Apollo was the sun if I never saw the sun nor felt its warmth in the first place, after all.
There is also the weight of the perception versus the weight of the experiences. Copernicus, to stick with the sun analogy, would have grown up under the pretense of a geocentric universe. However, his observations towards the stars overcame his learned experiences, and perception won out, creating the very first experience of a heliocentric universe.
The only reason we look on the Roman version of me as ridiculous for believing that the sun is the god Apollo is because our species has the collective experience of the Copernican revolution. It is shared in our media, literature, dialogues concerning the universe, etc. and so our experiences regarding the reality of the sun are quite weighty.
For example, if today I saw the sun blip from one part of the sky to another, seemingly teleporting across the horizon, the weight of my experiences would override my perception. I would assume I had fallen asleep, and woken up at a different time of day, or that it was a trick of the light that caused me to misperceive the solar blip. I would interpret these perceptions, and therefore reality, in such a way that would make sense with regard to the experiences I had accumulated over my lifetime. I would discount my perceptions as false, and carry on as if they had never happened, leaving reality unaltered.
However, if new experiences availed themselves to me, for example if I learned that others than myself had seen the blip, if it made the newspapers the next day, scientists were exclaiming bafflement, etc. then the weight of my original perception would increase and reality would shift to accommodate these new experiences.
One might argue that this subjective reality works only on an individual scale, and when joined into a collective, such as through peer-reviewing, or replicability, this would give a glimpse into a more objective reality. However, I would disagree and say that a collection of subjects is still subjective. The addition of new perceptions and a greater amount of experiences still falls within my original definition.
New ideas are frequently met with derision and ridicule because of that very same collective agreement of experiences among a society that dictate what we call reality. Copernicus and Galileo were keenly aware of that distrust of new versions of reality, even though today we dismiss those who condemned them as ignorant. Was it because the Church was afraid of losing its tenuous monopoly on the truth, or was it for the same reasons that today we would mock and scorn someone who adamantly claimed that leprechauns existed? Even potentially lock them up in the loony bin? Is it because there necessarily cannot be leprechauns, or is it because humanity has never had a weighty enough experience of leprechauns in order to accept them into our collective reality?
Even if you disagree with me, and believe that not only is there some kind of ultimate, objective reality, but human beings can access it (outside of our sensory perceptions and our experiences, (?)somehow(?)) then that is only because the experiences in your life have given such weight to that “objective” view of reality that your perception of my ideas does not hold up against them.