Menachem, please provide one person called a navi in a serious context(not the raavads insult of the rambam calling his words divrei nevuah sarcastically) and I’ll take the idea seriously. What we find poskim sometimes doing is euphemisticly calling anotjer gadol’s writings nevuah because they can’t find a source for it in fhazal; the raavad used it sarcastically, they use it respectfully, but it’s clear that that’s their intention.
Find one place where rhe rishonim say “so and so was a navi” or “this person heard the dvar Hashem” or the like – you won’t find it. Anywhere.
As for the mishi….batla….those are discussed. They mean that the highest manifestation of anivus, yirah, etc…are gone. That’s because it’s obvious that one can fear Hashem in any time and place; those gemaras aren’t referring to a specific phenomenon. Nevuah is a phenomenon which chazal are saying no longer happens. The rishonim do not say on that gemara “nevuah isn’t so common now,” it’s been taken as a given by the rishonim and achronim for 2000 years. Universally.