Yes, that's how things work in the real world. When one destroys their credibility over and over again, nobody even bother to takes them seriously. That's what Rebel News did.
You never read the Boy Who Cried Wolf in elementary school? It's the same concept. If you're not familiar with that story, then re-read Usopp's story in East Blue when he kept lying to everyone in his village about pirates, similar concepts.
Just answer a simple yes or no question, do you think an extreme right and anti-science media outlet is a reliable news source, yes or no?
You pick one of the worst media outlets and then get upset when people won't take it seriously. Surely you can any half decent news media outlet preaching what you say?