If I have a gallon can of white paint and I put one drop of black paint into it, is it still white?
Yes, of course it’s still white. Because the word “white” is a visual descriptor. It’s not a descriptor of, say, temperature, or density, or weight, etc. It’s a word to describe its most obvious visual characteristic, which we can all see. Of course, it depends on the viewer’s eyesight, but since the majority of people see white as white, personal perceptions are irrelevant here.
What if I didn’t know it had black paint in it? Is it white because I perceive it as white? What if I keep adding drops of black paint into it one drop at a time, at exactly what point does white become grey and how do you decide where that is? Let’s say it’s grey as soon as you start to notice that it’s not as white as when started out. In other words, you make a judgement call based on your personal perceptions.
Clearly it’s pointless to plump for subjectivity when talking about such phenomena as colour. That doesn’t mean, though, that perception as such is always untrustworthy. It’s a mischief to suggest that it is.
“Correct" (like “white") is a label that tells us how you feel about something, it’s not intrinsic to the thing itself.
Again, that way of looking at the world is not always useful. Outside the world of semantics, no doctor would arbitrarily triple the dosage of a medication just because the standard dosage didn’t “feel” right to him. If the literature specified 5 mg, but he “felt” that 5 is 10, the patient could die.