It wasn't a false narrative. They actually said in the show that Bruno wasn't a scientist and he only made a lucky guess. Which underscores the question about why they used it, but what they said wasn't false, and it didn't mischaracterize religion.
Regardless, the question at hand is why it should be a bad thing for a science program to be biased against religion. You seem to load more concepts onto the word "bias" than it actually has. Bias doesn't mean dishonest. I might have a bias to tell the truth, which would make that bias more honest. I might be biased towards a correct belief. Bias doesn't mean dishonest or wrong.
"Science should not have an agenda and should be free to follow evidence wherever it leads."
Yes, and that very thing puts it in opposition to religion, because religion does NOT work that way. That's the point. In being free to follow evidence wherever it leads, science is necessarily biased against religion which requires not doing that.
Is that a bad thing? No. Christianity is biased against Islam, which it must be, and vice versa. Capitalism is biased against Communism, by necessity. They are incompatible beliefs. Reason is biased against superstition. Science is biased against religion, and vice versa. It is the nature of the thing.
And again I state, there is no justification for a science program to be intentionally biased against religion or to mischaracterize religion in order to fit a false narrative. Science should not have an agenda and should be free to follow evidence wherever it leads. This Cosmos series is a mixture of Hollywood and science – and Hollywood comes with its own agenda , beliefs, and ‘faith’.
With the addition of - Go peddle that crap to someone else 'cause I ain't buying.