It is indeed said The Silmarillion that that harrowing scream of Morgoth can indeed still be heard in the Ered Lómin and the region east of Losgar.
“And all the waste between the hills and the sea was filed with a clamour of voices as in anguish”
It was said that if any cried aloud in that region, the cries of Morgoth would be awakened, a word I find so wonderfully creepy. Morgoth himself might never return to this region but there is something of him there, waiting
Though it was likely not the only reason, I wonder if this is part of why this region remained largely uninhabited with only some of the Sindar occasionally travelling through there.
Perhaps it enters into the folklore of the Noldor and Sindar of Hithlum, a portent that must be avoided. Perhaps there truly are ill effects of hearing the shadows of that scream; the echoes of Morgoth follow those that awaken them, invading dreams, bringing an unquiet mind.
Perhaps only when Beleriand flooded, the echoing rage of a god was finally swallowed forever. Perhaps it remains still in crevices and caves. The world is Morgoth’s Ring, after all.
