I mean, I'm not an expert on any of this, but I'm looking it up and you seem to be quite wrong:

> Looking closer, this was not some isolated UN estimate. Instead the UN was generating estimates every year, and the 2022 study was conducted differently because of covid.

It seems it was indeed an isolated UN estimate, done in conjunction with the University of Southampton, conducted because the country's census was cancelled, supposedly due to COVID. Yes the UN provides yearly estimates, but it looks like this was a separate, one-off research project.

https://en.wikipedia.org/wiki/Demographics_of_Papua_New_Guin...

You can see the sources Wikipedia links to.

> Subsequent UN estimates also went back to the original numbers. Also it wasn't a report that was buried, the numbers were released in 2022, they were revised down in 2023 after the UN conducted its next study. Seems like quite the omission.

No, it looks like the report's numbers were never officially adopted at all. You can see the yearly figures here, there's no bump at all:

https://population.un.org/dataportal/data/indicators/49/loca...

As far as I can tell, all reporting states that the report remains publicly unavailable. The numbers weren't "released", they were leaked. That certainly seems "buried" to me.

> While arguments presented without evidence can be dismissed without evidence, sure here's the CIA estimate for the population which is in close agreement with both PNG's internal estimate and the actually adopted UN estimate.

The CIA World Factbook isn't trying to independently maximize accuracy using new techniques. They're mainly relying on official data provided by the countries themselves:

> Estimates and projections start with the same basic data from censuses, surveys, and registration systems, but final estimates and projections can differ as a result of factors such as data availability, assessment, and methods and protocols.

https://www.cia.gov/the-world-factbook/about/faqs/

Again, I'm not an expert in any of this. But nothing in the article appears to be contradicted by public reporting I can find. It provides additional information, you're right that I don't know how the author got it. You say you "can find contradictory evidence with a 30 second google search." But you haven't, you've actually given a bunch of wrong or irrelevant information.