The former is a joy of the morning, seen only with the arival of day, a surprise, beautiful and subtle, not overwhelming, but spread over a large territory, covering everything, is reliant on no human agency, and likewise utterly out of human control, even in our modern times. The latter is entirely localized, something coming from one vessel, likewise entirely a human thing, as prosaic and boring and unevocative as pouring out some flat Coke. Very importantly, “pour out” in modern American English connotes disposing of a drink or other liquid no longer useful or desired. The related “outpouring” is only heard in religious language these days, so is still somewhat safe. But the two, “dew” and “pour out”, are by no means at all equivalent.

The Latin means “dew” so the English should say “dew.” It’s immeasurably more poetic, and appropriate.