First, if they were Minoan that would have been recorded in the annals of civilizations like Egypt and others which kept good records. The Egyptians and others of the Eastern Mediterranean had long links with Crete and the Minoans. It doesn't stand to reason that the Minoan could launch such a large movement (in the sense impact so many areas of the Eastern Mediterranean) and no one notices.
Secondly - the nature of the sea peoples attacks, assaults suggests a group of people moving, migrating - not looting and returning. If the Minoan were doing this - why would they not return with their gathered spoils to their homeland. If they did return - where is the physical and archeological evidence?
Those are the pressing ones that come to mind first. There's also the question why would the Minoan embarknon something so foolish as invading Egypt. Egypt was what a hundred times bigger? If you failed - first you'd expose yourself to retribution and secondly - you'd weaken yourself severely leaving you exposed to others.
Because of Egyptian inscriptions. If it was only one group, why do Egyptian inscriptions list 5+ groups? Here's the relevant article section:
"The Philistines (known to the Egyptians as the Peleset) were among several groups listed as the Sea Peoples by the Egyptians. The other Sea Peoples were the Tjekker, the Shekelesh, the Ekwesh, the Shardana, the Danuna, and the Weshesh. An inscription on the tomb of Ramses III reads:
“The foreign countries made a conspiracy in their islands. All at once the lands were removed and scattered in the fray. No land could stand before their arms, from Khatte, Qode, Carchemish, Arzawa, and Alashiya on, being cut off at [one time]. A camp [was set up] in one place in Amurru. They desolated its people, and its land was like that which has never come into being. They were coming forward toward Egypt, while the flame was prepared before them. Their confederation was the Peleset, Tjekker, Shekelesh, Danuna, and Weshesh, lands united. They laid their hands upon the lands as far as the circuit of the earth, their hearts confident and trusting.”
Arzawa is in western Anatolia, Khatte is the Hittite realm in central Anatolia, Qode is Cilicia in modern southeastern Turkey, Carchemish was a city on the banks of the Euphrates River, Amurru was an Egyptian vassal in northern Lebanon and coastal Syria, and Alashiya is Cyprus. The Danuna are the Greek tribe of Danaans referenced by Homer in “The Iliad”. The ruins of the Hittite capital of Hattusa have been excavated, and the destruction of the city was between 1190 and 1180 BC. In the same decade, the city of Troy was destroyed as well, likely in what is remembered as the Trojan War.
The identity of the other groups is less certain. The Mycenaean Greeks are known to have had contact with the EEF peoples of Sardinia - the Nuragics - from pottery finds. The etymology of Sardinia’s name is unknown, but the the name predates the arrival of the Phoenicians. The Shardana referenced by the Egyptians as being among the Sea Peoples may be Sardinians, Nuragics recruited by Mycenaean Greek sailors for campaigns of plunder and conquest. The Sardinians certainly knew of the wealth of the east - their copper, valuable in the Bronze Age as one of the ingredients for bronze, originated from Cyprus.
Similarly, the name of the Shekelesh may refer to the aforementioned Sicanians in Sicily. Alternatively, it could refer to the Italic-speaking Sicels (relatives of the Romans) who invaded southern Italy and Sicily in the late 13th or early 12th century during a massive drought in their home, the Po River Basin of northern Italy."
For one there is no "the" Sea People. It is a uselessly broad term like barbarian, stranger, or foreigner. It is a xenophobic mark from the insular to those not known and liked as opposed to a group in itself. The users of such a term essentially prided themselves as land based empires.
The Minoan civilization had been on a downward arc for several hundred years (i.e. since 1600-1500BCE, including possibly being conquered by Mycenaeans around 1400BCE) by the time of the Sea Peoples' antics (about 1200BCE).
