Even in ancient languages the plural used to identify a group, as in this case, quite possibly means that the ‘Sea Peoples’ were a combination of different ‘peoples’, like a mongrel race, consisting of Minoans, and others, when their island(s) were destroyed....................
Everything I have read indicates they were.
Egyptian records lump them together as a group. I think they even called them the “Sea People (or Peoples)”. They just appeared on the coast kind of like 1200 BC Vikings.