> It was factual that the earth was 6000 years old, until it wasn't.
This is the opposite of the example you seem to think it is. The Earth has always had the same actual date of origin. If it is not factual now that the Earth is 6,000 years old, then it wasn't before either. The whole argument here is that people's perceptions and reality can in fact be different.
I would argue that factual past is unprovable without some sort of visual evidence, and even that can be manipulated...especially with AI on the rise. The problem with your point is that EVERYTHING is parsed through your perception, and you can just as easily make the point with the same logic that you can't prove that what you are currently experiencing is present reality.
What actually happened is unprovable without some layer of trust once the event leaves the affected. For example, I ate a grapefruit for breakfast. That is a fact. However, I have tossed the peel away and I am communicating that I ate it with a stranger over the internet. For all you know, I could have eaten cookie crisp. If you and enough people get together and collectively believe that I ate cookie crisp, the public belief will be that I ate cookie crisp. However, that does not change the fact that I ate a grapefruit.
Given that, there are two, and only two possibilities:
Either
-my perception of reality is inherently opposed to objective reality
or
-the world, for some reason, is gaslighting me into thinking I ate a sandwich and the objective reality is that I ate a grapefruit.
See, my problem with this "philosophy" that objective reality does not exist is that it enables abusers. Have you ever seen the movie Gaslight? Its a classic. This poor woman lives with an abuser...someone who is committed to making her think that she is crazy. He contradicts everything she does and says, sets up evidence to objectively prove that she only imagined herself doing it, and keeps her under his thumb through those means. In the end of the movie, its revealed that none of the evidence is real and that she is sane. To combat against these types of people, its important to be sure of your own reality and only change if evidence is overwhelmingly pointed in the opposite direction. Even then, question these changes in belief heavily. Otherwise, you will believe just about anything anyone says.
No, that was never factual. Radiocarbon dating gives us evidence, factual without the lense of perception or opinion. Saying the earth is 6000 years old is just repeating propaganda.
Perception and reality are not in fact the same thing.