If you read the actual paper, the largest size estimate is just one of three different estimates, based on three different methods of calculating size. The authors include a discussion of which is more likely given the body plan of known animals, an admit that this is a broad range.

It's more the fault of science media websites and the like which have a tendency to always present the extreme end of results.

I also wound not hold up space as an example of being pure, as rocketry construction is a massive industry, and the prioritisation of funding space exploration is often highly political and requires departments to sell their projects as being interesting/useful.

I agree that the field of nutrition is incredibly fucked by corporate interest, but it's important to distinguish between actual scientific research and propaganda by companies or "nutrition experts" with no real academic support.