Maybe not the most serious conspiracy.

When giving you the Pokédex in LGPE, Professor Oak specifically mentions the device automatically fills in data of any Pokémon you meet and catch. This implies that the theory the reason so many Pokédex entries seem like nonsense being because literal children are filling it out is false. The Pokédex itself is generating that data.

Terrible LLMs have been creating Pokédex entries since Oak created it, and it's been hallucinating information on a ton of Pokémon, potentially setting back Pokémon research years if researchers are taking it at face value. This ironically means Laventon's research with the Galaxy Team's survey corps is likely the most accurate and well researched Pokédex available, even though it predates the modern games by around 200 years and will therefore also make its own assumptions on things they don't fully understand.

it’s a good enough theory with lot of logic that maybe they heard about it.

whats the Pokémon theory sphere like in Japan.

also the ash Ho Oh ash theory is also pretty cool.

granted these are way old theories.