Why do major media outlets say "conspiracy theory is unintelligent" when history is plastered with conspiracy?

I have have degree in history and everything is a conspiracy theory.

That Putin rigged the election is a conspiracy theory.

That the Taliban took over Afghanistan is a conspiracy.

That Catherine the Great murdered her inept husband to claim power over Russia is a conspiracy theory.

The many Balkan princes who were killed were killed as apart of a conspiracy.
Why do major media outlets say "conspiracy theory is unintelligent" when history is plastered with conspiracy?
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