Achaeans: historical or mythical?

Is there a consensus about the real identity of Homeric "Achaeans"? According to
Thessalian genealogies, Helle:n had three sons: Do:ros, Aiolos and Xouthos
(father of Ion and Akhaios). Dorians, Aiolians and Ionians are well-known Greek
dialects, but there's no Achaean dialect. Could Achaeans be the mythical
counterparts of Arcado-Cypriotes? Or some Pre-Greek people?
I've ever thought in how Greek genealogies were "built". Where did this set of
Dorians/Aiolians/"Xuthians" come from? It seem to be an "Aiolian" idea, since
Xouthos's and Doros' descendancy is too opaque.

We can cluster epic genealogies in four main groups:
1. Deucalionid - mainly Thessalian, Iolcos, Argonauts, Prometheus, Amphictyon,
Aeolians, Pylos, post-Perseid Argos, etc.
2- Phoronid/Inachid - Argos, Crete, Cadmean Thebas, Egypt, Heraklids, Perseids
3- Tantalid - atreids, Pelops, Mycenes, Menelaos, Thyestes
4- Cecropid - Athens


JS Lopes