I replied down thread to a similar point you made - I think you are redefining "believe" to the point where it loses value.

Responding as if someone is acting in good faith means that

- you believe that

- they believe that

- they are true

On the other hand, if you believe someone it means that

- you believe that

- they are true

Using "believe" to mean the first situation only makes everyone's meaning less clear.

As I said in response: I don't really care what HN thinks about the term: the experts in the field recommended it.

That should give you pause when you claim (incorrectly) that a such a narrow usage of language is correct.

As speakers of English, we ARE the experts in the field, and the vast majority of us don't agree with you.

That's more like "take them serious" on the "believe" (i.e. "It's true, do something!") - "take them serious" (i.e. that could very well have happened, let's check this out) - dismiss (i.e. yeah, yeah, let them talk, could never have happened) spectrum.

All three points lead to different actions and the one in the middle seems to be the most appropriate.