Can you provide an example of a scientific field or topic being hijacked (for years) by certain viewpoint (later proven wrong), where such a clique slowed down progress by exercising their political/economical power?

Breakthroughs which require a major rethink qualify; plate tectonics was a very tough sell for twenty-five to thirty years, before enough people managed to follow the data.

The clue in this area is when politicians hand-select scientists; you can always find a few on the fringe whose PhD’s look as good as any other if you’re sitting outside the academy, and you can cherry-pick qualifying remarks from the real experts to mislead the unwary.

Climate science and evolution have enemies with enormous followings. The consensus in those is very clear: a) evolution is real, and b) so is the approaching catastrophe of climate change due to human injection of CO2 into the atmosphere.

You didn’t read it here first.