I think the Greeks understood that the truth is what you write down and I get the sense they looked around and went "psshh like the Romans are gonna contradict us" and YOLO'd into whatever the fuck facts they felt like fabricating. "I mean yeah the Spartans lost at Thermopylae but that's because there were eleven million Persians and also they were minimum seven feet tall" works just fine until you invent archaeology. As far as salsify and its ilk, let's call it "the sunchoke problem" - yeah you can grow it, yeah you can eat it, yeah you can cook with it, but when its competition includes Uber Eats it bloody better be worth it and we live in a society that went "ZOMFG RED DELICIOUS APPLES MUST DYYYYYEEEEEEEEEEEEEEEEEEE" because they weren't as flavorful as Fujis.
There's a lot of it in Greek writing, though it's also clear that they were pretty self-aware in that style. Iliad is chock-full of exaggeration-by-convention, Thucydides stresses at key places basically going "no, guys, I'm not saying this for effect like other writers usually do, it happened like that" and counts on reader not being gullible in that regard, and Aristotle disses on authors overusing these modes as immature and lacking. IIRC dissing on Aristophanes', since that was his thing. Plutarch often juxtaposes contemporary hearsay with plausible causes/effects, emphasizing a couple of times how the style of other (sometimes lost) authors muddled the events. It's kinda like how 'silver age' of Latin gets the rep of no substance and all-style, but that's because imperial absolute ruler changed the purpose of rhetorics from discourse to entertainment. They were aware what's being said when nothing is being told -- which Seneca corroborates in his writing while under banishment -- we're just left guessing what those nothings are about exactly. We typically read Greek tall-tales and think they were swallowing it whole, which I doubt they took too literally themselves. I don't know, sometimes the novelty of it is enough? Then again, I do admit to having rather plain palette, willing to favour texture to flavour."the sunchoke problem"
Yeah the issue with the Greeks and their fish tales is the Dark Ages. If it was written it was true. I've read a few accounts of the "transcription errors" in illuminated manuscripts that were basically performed to align the holy writ with the dogma of the time but the transmitted texts were God's own truth nonetheless. That whole "you should regard this as a rap battle not a Nature article" aspect of the ancient writers also has not trickled down to nearly enough popular science writers. Jane McGonigal quotes Heroditus a half-dozen times in Reality is Broken as if the dude was Walter Cronkite. As far as "novelty is enough" I mean... sort of? Depending on the context? There's this mythical idea that wasabi only grows on the southern slopes of Mt. Fuji and then only when watered by geisha tears under the watchful eye of Amaterasu. Then there's the reality that it'll grow like a goddamn weed from Northern California to Southern British Columbia. Then there's this mythical idea that you can grow rich by growing wasabi (check out that illustration!). Then there's the reality that everyone who cares enough to eat real wasabi can grow their own wasabi and pretty much everyone else is totally cool with 99 cents a pound dyed horseradish. Guaranteed, my neighbors wouldn't have made magnolia cookies if they hadn't seen it on Instagram. And guaranteed, anyone who attempted to market magnolia cookies would go bankrupt.