But, ok, this is my idea about how this works, and real climate change deniers have a different opinion.
You are spouting bs from the standard denier's playbook, exactly as one can find in the media feeds from the rightwing corporate authoritarian think tanks, exactly as one hears from the "experts" on Fox News and the "bothsides" media setups. Seriously:
everything you post on climate change is idiotic propaganda from the standard fossil fuel industry shills and Republican Party media feeds. Almost none of it is "your idea".
But the side effect of alarmists in the media presenting themselves as presenting scientific evidence is that scientists lose credibility.
There are lots of people like you, you mean - people who can't tell when they seeing an alarmist and when they are seeing a presentation of sober news.
That's true.
That's not much of a factor in the attacks on scientists's credibility in the US, though. In the US scientists have lost credibility largely through being slandered in the media by paid shills of the fossil fuel industry (or the tobacco industry, or the automobile industry, or agribusiness, or the Republican Party dredging for fundie votes, etc. )
These paid shills say stuff like this:
I believe that political sciences (sciences where there is a strong political interest in favor of a particular scientific result) look quite different. The grad students are poor, and, more seriously, they have no safe job at all. They have to look every two years or so for a new job or a new grant, else they are out. So, whatever they think, they have to care about what the mainstream thinks because the mainstream leaders have control over the jobs and grants. Thus, they have to follow all mainstream fads.
Standard US media feed wingnut vocabulary and claims bolded. None of this is "your idea".
Obviously, any informed and disinterested person would realize that the primary pressure on climate change science is the enormous political and economic power of the fossil fuel industry.
So these people would immediately see that the scientists who have been pressured to keep quiet are the ones working for Exxon et al (whose evaluation of CO2 effects thirty years ago would qualify as "alarmist" even today in the current wingnut vocabulary, but was kept out of the news), and the ones whose grant funding and good standing with their universities demanded that they not anger or threaten big donors and funders (such as the fossil fuel industry), and so forth.
But those paying the shills know that such informed and disinterested people are a minority, do not own or control major media, and can be drowned out.
That explains why the "alarmists" have been not vulnerable grad students cooperating with some fantasy mainstream, but established professors with tenure willing to spend years bucking serious opposition and well-funded personal and professional attacks - people who are difficult to retaliate against, people who have actually done the research and can back up what they say.