True Left

"The curator reduces the amount of knowledge in circulation by refusing to include low-quality information in the collection."

Curation is the accurate term for the process that present-day rightists wrongly refer to as "censorship" (as done by private organizations, which by definition is not censorship). We should use this word more! Every time rightists claim that they are being "censored" by [insert platform here], we can tell them they are in fact being curated

"There is more information in circulation than any human can possibly read/view in a single lifetime."

This is a very important point. A long time ago, I proved that it is generally impossible for any two communicating people to fully understand each other unless both are exposed to essentially the same subset of information. This is because, as soon as two people are exposed to different subsets of information, it is generally impossible to determine with certainty whether a disagreement between them on a given issue is due solely to difference in personality, solely to difference in the information they possess on that issue, or some particular combination of the two.

This is why civilizations which Westerners would call "less knowledgeable" actually enabled people to engage in higher-quality communication. Having less information in circulation, communicators could much more quickly diagnose the source of any disagreements. Westernization, in injecting so much more information into circulation, ensured this was no longer possible. People today are still aware that they disagree, but are no longer able to easily figure out why. (Instead, they are merely advised to be "tolerant".)

"I discovered these old scientists had better arguments against ethno-tribalism than present-day biologists. Yet no mainstream biologists and sociologists seem to know about this"

Please present these somewhere when you have time.

"Especially with the tendency to view history as a "march of progress", they view it as below them to examine "outdated", "backwards", and "crude" information from the past."

We could even argue a parallel between this and its counterpart in finance where savings are devalued over time by an utterly insane phenomenon called "inflation". What you are describing could be called informational inflation.

"In their egotistical pursuit of producing their own "novel" knowledge"

This is driven by the ultimate Western academic prestige of getting a theory/equation/method/etc. named after oneself, thus having one's name immortalized. We could call this academic Achilleanism.

"Ironically, by continuing to produce "novel" knowledge regardless of its quality or purpose, they compound the problem by producing so much new information that it becomes difficult even for subject matter experts to study old information when they get buried by all the new information being produced.
...
In terms of truth, it is easier to demonstrate and do damage control on the falsehoods from a small collection of information that is not growing rapidly, compared to the deluge of information pumped out by the Western academic system. During the effort it takes to demonstrate a single thing to be a untrue, a hundred more pieces of information take its place."

This is one of the recurring themes of Western civilization!

"Any thoughts on how to discover and what to do if the subject-matter expert is actually a propagandist trying to obscure the truth?"

Self-proclaimed subject-matter experts should only be recognized as subject-matter experts if their treatises accurately represent all requested opposing arguments to the narrative they themselves favour. Intellectually dishonest experts tend to include strawman opposing arguments while either ignoring or misrepresenting arguments that are actually dangerous to their narrative. But if those who do this are called out on it, they must either respond by incorporating accurately the opposing argument offered or else fail to be taken seriously.