For how long did "Roman" and "Etruscan" persist as distinct, living cultural identities in ancient Roman society?

I'm not a massive expert on Etruscans or anything, so if someone has some more specialised knowledge, please chip in. I don't think we can pinpoint any specific time when Etruscan identity stopped existing, because of the problems of defining what cultural identity is and how do we track the existence or disappearance of cultural identities with the sparse evidence we have.

The 'Romanization' of Erutria began slowly after the conquest of Veii in 396 BC. From there on, we can see changes in Etruscan material culture, religious rites and language that betray the adoption of Latin influences as a result of Roman expansion and implementation of Roman infrastructure (road networks, centuriation etc.). This process intensified with the defeat of Caere by Romans in 274-3 BC, after which all of Southern Erutria was under Roman influence, and the full integration of the Etruscan areas into the Roman sphere was when Augustus created a Roman adminstrative region Regio VII out of them. During the Middle Republic, it seems that some Etruscans still deemed it important to articulate a distinct cultural identity from the Romans - for example, see Michael Taylor's paper that points out that the Etruscans in Roman military preferred to use distinctly Etruscan style funerary monuments that stood out from those of their Latin comrades. By the time of Augustus, however, Etruscan culture was almost gone; the language was hardly spoken and written, and the old characteristics of Etruscan society had disappeared. For example, the near equal status of women slowly disappeared as the Etruscans started following the social norms of Roman society, as we can see from the diminishing visibility of women in Etruscan art and funerary iconography, and by the early empire we simply cannot distinguish an Etruscan tomb from a Roman one. We know that the Emperor Claudius (10 BC – AD 54) was perhaps one of the last people who could read and write Etruscan, and he compiled a history and dictionary (Suetonius, Life of Claudius 42.2; these works are now lost) of the Etruscan language when it was dying out. We also know from Suetonius (Life of Claudius, 26.1) that the first wife of Claudius, Urgulanilla, was Etruscan. She was just one of the few notable people in late Republican and Julio-Claudian Rome that the literary sources call 'Etruscan'. What it meant to call someone 'Etruscan' during Claudius' time or Suetonius' time is unclear - at this point almost no-one spoke the language and centuries of intermarriage most likely meant that there weren't any 'pure' Etruscan lineages anymore. Could Urgulanilla perhaps still speak Etruscan, or was his family simply promoting its identity as Etruscan?

Because, long after Etruscan culture was completely assimilated to Roman culture, many Roman families liked to lay claims to Etruscan ancestry and early Etruscan kings since it gave the family status as ancient elite. For example, this chair known as the Corsini Throne is as late as 2nd century AD and it was discovered from the villa of a wealthy Roman family. Its made in an archaic, Etruscan style that is clearly meant to promote the Etruscan heritage of the family - whether there's any truth to their claim or not is not known, or probably not really important. Also, there were priestly colleges and divination experts that continued to practice a distinctly Etruscan form of rites, based on ancient Etruscans texts, all the way to at least 5th century AD (and these people might have actually preserved the knowledge to read Etruscan even after Claudius).

So, in conclusion; people continued to identify themselves as 'Etruscans' and use Etruscan cultural symbols long into the imperial period, and some aspects of the Etruscan culture lived on and continued to be celebrated specifically as Etruscan culture. But, I'd imagine the culture as distinctly different from Roman culture - and people living according to that culture - died out already during the Republic.