Theories about the collapse of Bronze Age civilizations have been around for a long time, and the Egyptian inscriptions about "Peoples of the Sea" have been known for a long time as well. Some of the destructions (such as of the Hittite capital) are probably earlier than 1177 and had to blame on sea raiders. Pylos' destruction is usually put about 1200. The fall of Troy is probably well before that.
“Had to blame” should have read “hard to blame”