Not a historian, but the obvious explanation is that Crete was the centre of the Minoan civilisation, ‘the first advanced civilisation in Europe’ [0]. The only other scripts in use at the time were various forms of cuneiform in Mesopotamia and Anatolia (for Sumerian, Akkadian, Hittite etc.) and hieroglyphics for Egyptian, all of which have been deciphered. We have far more evidence for those scripts than we do for the various Aegean ones.
Makes sense. Another dimension to this is that Minoan language does not appear to have had any resemblance to any form of Greek. The most ancient cultural artifacts from Mycenae seem to be of Minoan inspiration while Crete itself seems to have had intrusive Mycenean characteristics until it was completely supplanted by the Mycenean.
[0] https://en.wikipedia.org/wiki/Minoan_civilization