The good thing about scientific consensus is that it changes when compelling evidence is produced. Most scientists will not stick with an idea just because it's what they always thought before, unlike many politicians. Of course scientists are humans too and may be stubborn. If your reputation is based on a discovery that gets outdated you might be slow to change and those with authority can influence opinion. We can't say that every 'rebel' is right though. News spreads a lot quicker than it did 100 years ago.
As always, extraordinary claims require extraordinary evidence.