Reverting postmodernism

Is it just me, or has Western culture kind of forgotten that postmodernism was ever a thing?

(Feel free to correct my facts or definitions. I am dabbling in a field about which I know little because I know no one else who is. Yes, I know that this reasoning is circular. I could say that this post is a research effort weaponizing Cunningham's Law, but that would depend on this blog having readers. So I am just writing because writing feels like the right thing to do.)

According to my understanding, we used to operate based on Modernism. We believed that we could understand the world and tweak it for the benefit of humanity, or for whatever it was that we wanted.

From modernism, we logically discarded the belief in the inherent value of the natural as opposed to the synthetic. (I am still looking for the term for this philosophy; "naturalism" is already taken.) We did so because we had already rejected a designed universe, and we figured that evolution's ad-hoc systems should be easy for us to improve. So we prescribed invasive and radical medical procedures freely. These had some unexpected side effects; science advanced and picked fights with its past selves.

And then we rebelled against the previous generation, discovered that nature is a lot more complicated than we thought, and popularized holistic, natural remedies to avoid the consequences of hubris. At some point the literary deconstructionists had a collective existential crisis and started questioning the preconditions of intelligibility as applied to communication and arrived at some sort of auto-simulation hypothesis. And thus Postmodernism came to replace Modernism. We determined that truth was unknowable and therefore relative. We heard "I think, therefore I am" and thought, "How interesting that my perception has told me a story about a man called Decartes. I wonder what this reveals about the pulsing mass of tubes that lives inside my skull. Or perhaps there are no tubes."

And now, with COVID-19 and global warming and whatnot, we are using "anti-science" as a slur, which clearly reflects a belief in some sort of absolute truth. Transhumanism and body-modding seem to be popular. "Natural remedies" means "anti-vax" and "anti-vax" means "conspiracy theorist". So we seem to believe that we can reliably understand and restructure at least the human body. I guess we are back on modernism now?

So are the doctors or the literary critics correct? We cannot reconcile modernism and postmodernism, at least if postmodernism precludes epistemology. If human communication cannot reliably indicate the intention of its author, then science is impossible since we rely on the discoveries and publications of others. If we are going to operate under the assumption that we can know things, should we not say then that the deconstructionists are wrong? And if the deconstructionists are wrong, maybe we should reconsider postmodern literature? Why does no one acknowledge the apparent contradiction? I cannot even find anyone criticizing literary deconstructionism with an Internet search.

I am confused.