A lot of theories exist regarding the Bronze Age collapse in Greece: the Dorian invasion, climate change, overpopulation, the Sea People, internal strife/uprising. If I am not mistaken, the Dorian invasion is now rendered the least probable cause for a variety of reasons. The destruction of palaces shows a southern trend (from Thebes to Pylos) in a 70-year period. Scripts from Pylos state they were preparing for war, but without specifying the enemy. Could anyone elaborate on the causes of the collapse? I find it wildly intriguing.
More can be said on the matter, especially since it's a period that could use more examination; in the meantime, however, you may be interested in u/UndercoverClassicist's post on the Late Bronze Age 'Collapse', which won Best Of June, and well deserves that accolade.