yes, that's correct. But we have to think about this!
First we have the Pelasgians mentioned by Homer in different regions, from the borders of Thracia to Crete, even in Thessaly and Epirus.
They are mentioned by Aeschylus in Argos, they are mentioned under the name of Tyrrhenoi. heketaios and Akousilaos called them pelopponesians. another source is Herodot, who reports them as well in Attika. The "best" is Ovid, who calls the mycenians Pelasgians. and i could go on. I found a nice map at the english wiki
The Lelegians are reported in Little asia, the Aegaeis and even in the Lokris, Boiotia, thessalia and Messenia.
So let's suppose they were the native population before the Greeks arrived. Their arrival is supposed to be in the beginning of the 2nd millenium BC. The mycenian culture originated around 1750 BC and lasted to around 1000 BC. The only linguistic evidence we have is an old form of Greek. Of course we may believe, that a Greek nobility ruled about Pelasgian subjects and explain the greek linguistic relicts by such explanation, but shouldn't we expect a Mycenisation, even linguistic? Is it possible, that greek Mycenians rule a country for 700-1000 years and the main parts remain their native ethnic structure? the only thing that could be possible is, that the Mycenian culture was polyethnic and that the greeks were just in a minority, but is this the most probable explanation?
So if we believe, that the mycenians were greeks, how can e.g. the pelargikon be of pelasgian origin, if it is from around 1300 BC? at those time we should expect already mycenian greeks. what did the hellenes after 700 BC really know about the native population? Did they really had informations about times, dating around 1000 years back?
So here my consideration starts, what is, if the Pelasgians and lelegians are not the native population before the Mycenians, but the non-greek population of Greece, before the hellenic ethnogenesis after the 8th century BC? that would perfectly explain, why they weren't wiped out by Greek mycenians and are nevertheless known by post-homeric hellenes.