It's something that should be evident within the west, given we're constantly lied to by those presenting themselves as authority, experts, scientists, etc, including when it comes to gender, race, but also various other things. While "truth," whatever that meant, can exist outside of society, all truth that exists within society is dependent on it and shaped by power. Some truths are closer to reality, as possible that may be, while others are outright fiction, including construction of individualism that has existed within the west in last two centuries, equality, "freedom of the press," "democracy," and other things many believe exist, when they are merely illusions.

That whole paragraph demonstrates an incapability of discerning the difference between truth and ideological dogma. At which point I guess it makes sense why postmodernist nonsense might appeal.

Saying some truths are closer to reality than others is some Orwellian "Some animals are more equal than others" bullshit. Truth is reality, that's axiomatic. Nor are truths dependent on or shaped by power, they are independent of society, what you're describing there is dogma. Some dogmas are more true than others, dogmas are shaped by or dependent on power to exist.

By 1770 science had more than two thousand years of history behind it, and yet it had never once brought about any marked increase in human happiness.

Holy fucking mother of nope. I'm pretty sure people were a lot happier to not be starving or dying in agony of the fucking pox nearly so often, what a boldly absurd claim.