How many armor soldiers did the Roman soldier bring to the battlefield

[Condottiero Magno]

There is no evidence that segmentata was worn by anyone except lower ranked/classed soldiers. It is exactly the same as medieval munitions plate. It was only worn by those who couldn't afford anything better.

What are you drawing on here? Has the theory appeared in any published sources we could refer to?

Most finds of segmentata, I believe, come from legionary fortresses (Caerleon, Leon, Chester, Carnuntum), or from sites like Kalkriese that probably relate to legionary use. The segmentata from Gamla was being worn by a soldier of Legio V Macedonia. There are also a few segmentata bits from what could be auxiliary contexts, but most finds from auxiliary forts have been mail or scale. If segmentata was as low-grade as you suggest, would the pattern of evidence not be the other way around?

It's hard to argue with a mail supremacist...

The last time I partook in a LS discussion, DH changed the goalpost.

Any pagan or two with an ounce of skill could fashion wire into riveted or welded rings, explaining why mail was ubiquitous, cheap and easy to maintain. Why don't we see any depictions of higher ranking officers in mail? Could it be that it was the equivalent of medieval munitions armor? In contrast manufacturing LS required specialized tooling and maintenance difficulties required knowledgeable people, which is why surviving examples are rare and probably not as common if you were to rely on art - John Coulston's book on Trajan's Column might have details, if it's ever published. Some 250 years of use and modifications and upgrades, only to be abandoned over the course of the Third Century Crisis and the creation of state run factories. If it was so cheap, why wasn't it in continuous production, especially with the expansion in state run manufacturing?