But lots of uninformed and ignorant people don't go to Wikipedia for their takes on contentious topics, do they? It seems to me that the climate change denialists are capitalizing on that.

One of my mantras is: Bad people sometimes have good points. And it sucks when they do, because then they use that as leverage for all their bad points. Climate denialists have all bad points on climate, but "Wikipedia can't be trusted on contentious issues" is unfortunately not a bad point, because it's entirely true.

Concerning doing your own research, are you reading all research paper on all topics in the world? Or do you sometimes rely on an authority or scientific consensus, exactly as Wikipedia does?

If you had wanted suggestions for gradual improvement, I'd say wikipedia would be better with a "high stakes" template to a lot of pages, with blunt language about idiots fighting over defining the objective Wikipedia position on issues.