nit: Only people can be incredulous. Well ok, dogs etc too. It means (of a person) "not wanting or not able to believe something, and usually showing this".
People are avoiding "incredible" for its dictionary meaning nowadays because it has morphed into a generic intensifier.
In a few years that will pass, and people will not say extremely silly things like "incredibly honest" anymore. But they will necessarily take up saying other equally silly things.
Thanks!! "Generic intensifier" is a very useful label, e.g. it's been driving me nuts how "literally" is used so frequently and inappropriately, on HN and other places. It's become a generic intensifier. But these words that cry wolf lose their..Ah well, this is what language evolving looks like I guess - like it's going downhill! But it's like Reutersvärd/Penrose stairs, only appearing to descend.
You are tripping over the Recency Illusion. As with almost all complained-about English usage, abuse of "literally" began (literally) centuries ago.
British newspapers regularly host shrill complaints about language degradation in the Colonies, but in every single case the reviled usage turns out to have started somewhere in England, typically before the colonials went. That shouldn't surprise: there is overwhelmingly more variability in English usage in England than the sum total in all other places.
It would not be at all surprising if "incredibly" went through a similar cycle 200 years ago. For a time, "nice" meant "stupid", before it meant "precise". For a time, "plausible" meant "implausible". Just be glad abuse of "exponentially" has fallen off.
Maybe, or maybe it is an unprecedented recent spike. We're both guessing, I suspect.
[5 minutes research later] Well, there is this measure of the frequency of 'literally' in books in English since 1600. (Although I meant in speech and online comments)
Which does seem to possibly support the 'unprecedented spike' hypothesis! A huge surge since 1990, the largest ever, the word is now used twice as often as in books in 1990.
Looking at examples from 1800-1820, during the 2rd biggest surge, which lasted around 100 years centred on 1840,
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A modern confounder is that copy-editing activity has declined along with the cost of publication, so that misuse that previously appeared much less in print than in oral discourse now evades scrutiny. Transcripts of court testimony would give a better sense of how people spoke.
Nonetheless, from your link I find in 1812, "was literally bathed with sweat" and 1810, "it shall bruise thy head, and thou shalt bruise his heel. This between the woman and the Serpent is most literally fulfilled ."
In a few years that will pass, and people will not say extremely silly things like "incredibly honest" anymore. But they will necessarily take up saying other equally silly things.