Somewhat unusually, the Etruscan writing system is completely understood, but the Etruscan language is not. With the early Cypriot script, archeological linguists can guess that the symbols in early Cypriot writing system corresponded to the same pronunciation and orthography as they did when later used write a dialect of Greek (which is deciphered), but there is no assurance of that. With Etruscan, they are certain of the writing system. Not only do they have a small number of bilingual texts, but they understand very well both the alphabet it came from and an alphabet that came from it.
The Etruscan alphabet came from the version of the Greek alphabet used on the western Greek island Euboea and was shortly afterwards adapted by the Romans to become the Latin script. Note that the Euboean Greek alphabet did not have omega, but used a character for the “s” sound that looked more like an “s” than a sigma. They later started using a glyph that looks like a modern “8” for the “f” sound, but only after the Romans adopted their alphabet.
The Etruscans got the alphabet from the Greeks early enough that the Greeks had not yet settled on which direction they would write. Etruscan, like Phoenecian, was written right-to-left most of the time. Many Etruscan letters “look reversed” to Latin-script readers for that reason. Occasionally, Etruscans would write boustrophedonically.
Part of why Etruscan hasn’t been deciphered is that it (again!) appears to be a language isolate, and there weren’t that many textual examples. Worse, many of the examples of Etruscan texts are on tombstones — not the most auspicious place to find bilingual texts or dictionaries.