In "The Knight and the Blast Furnace", Alan Williams uses Vickers Pyramid Hardness as a proxy for how good a material is at resisting penetrators, and the tests he performs in the same book largely align with that conclusion. On p. 5-6 he notes the range of VPH for bronze as 110-270, depending on cold working. On p. 17-18 he gives the range of 100-180 for armor-quality iron (depending on slag) and 180-260 for low-carbon steel, increased to 300-400 for medium carbon slack-quenched and up to 400-500 for medium-carbon, full-quenched, tempered steel of the sort that rich men in the early modern era could afford. In other words, bronze was superior to iron and comparable to low-quality steel.
When I look at bronze armor such as the Dendra panoply or the much later muscle cuirasses, they seem to provide decent coverage in the form of solid plates. For the former, the plates are apparently 1 to 1.5 mm thick, which is very thin compared to later plate armors but pretty comparable to a 14th century coat of plates, and with the same benefit of partially overlapping plates. Overall it seems either suit would provide good protection against cuts, thrusts, and arrows, comparable to iron or low-quality steel mail against the former and superior (due to solid construction) against the latter two. This armor, while used by "elites," also appeared to be reasonably common enough that most of said elites could afford it.
All that said: why is it that this armor more or less disappears entirely by the mid-late classical era? Bronze is harder to manufacturer and rarer than iron or even steel, averages about 10% denser than either, and requires foreign trade. I get all that. What I don't get is how complete the disappearance seems to have been when these suits seem to have real benefits over the iron and low-carbon steel mail that came to dominate the scene (plus, you can of course just use both). I would think that it'd stick around in some fashion for elites, but by the time Rome becomes a hegemon it gets consigned to the dustbin of history and never comes back. From the earliest point the Middle Ages are then all mail, all the time (plus some scale, with steel plate and transitional armor making its way in for the last couple centuries).
Or does it? Is the above accurate?
What is the actual reason it disappeared so thoroughly? Was it worse in practice than its paper stats made it look?