Lorica segmentata's use was eventually dropped by the Romans because of two main factors:

The first factor was it was highly specialised armour designed to defend against a certain enemy. This was against Celtic warriors who used long swords, designed to be used in a slashing motion, swung from up high and driven into the shoulder of the enemy (the Romans). Lorica segmentata provided extra defence to the shoulder region for this very reason. However, with the provinces in which the Celts and Gauls lived (northern Gaul, Britannia, Germania, etc.) becoming 'pacified' (a term very loosely meant here) and assimilated into the Empire, with their young men becoming troops in the Roman army, there was less need to defend against an enemy which was part of your army.

The second factor was the use of specialised, heavily armoured troops ceased during the third century. The legionaries, that had once carried out this role, came to resemble the auxiliaries, who were equipped with hamata and squamata. The auxiliaries were equipped for a more generalist role, being able to fight across the empire against many different enemies, however with the Constitutio Antoniniana in 212 CE, which granted all people in the empire citizenship there was no possibility for distinction between auxiliaries and legionaries. Coupled with the Romans adoption of the long sword and flat legionary shield meant the fighting style of the heavily armoured legionary moved towards the more adaptable style of the auxiliaries, and adoption of hamata by legionaries.

So it was not because of what provided more protection, although lorica segmentata provided a lot of protection, it was against certain enemies using certain weapons. If would not have been so effective against different enemies.

Lorica hamata was more labour intensive to produce than lorica segmnetata, however, it must not be forgotten that Rome was a slave-owning society, so they would not have cared so much about how intensive it was to create a piece of armour. on a similar vein, hamata would have been much easier to repair than segmentata. If a chain broke on segmentata it could have been repaired quickly with a piece of wire, whereas with segmentata, if that broke it would have taken a lot of time, effort, and resources to repair.

I am not too sure about how widespread plumata's use was. It was used by high ranking officials in the army (tribunes or above) so in theory it could have been widespread but only used by a small number of people, meaning it was less likely to enter the archaeological record making it harder to study. it was, however, very labour intensive to produce, for this reason, it was kept for high ranking troops to help them stand out of the crowd and also possibly encourage the troops. but it would have been impossible to mass-produce this armour to supply the army.

Pros and Cons:

Segmentata:

Pros: provided high amounts of protection to the shoulder area, easier to produce

Cons: provided no protection to below the waist, harder to maintain

Hamata:

Pros: provided more general protection, easy to maintain

Cons: harder to produce

Plumata:

Pros: provided strong protection,

Cons: very hard to produce and maintain

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Sources and recommended reading:

Bishop, M. C. & Coulston, J. C. N., 2006. Roman Military Equipment: From the Punic Wars to the Fall of Rome, 2nd edition. Oxford: Oxbow Books.

Bishop, M. C., 2002. Lorica Segmentata. Volume 1: A handbook of articulated Roman plate armour. Journal of Roman Military Studies Monograph 1. Braemar: Armatura Press.

D'’Amato, R., & Negin, A. E., 2017. Decorated Roman Armour: From the Age of the Kings to the Death of Justinian the Great. Barnsley: Frontline Books

Robinson, H.R., 1975. The Armour of Imperial Rome. London: Arms and Armour Press.

Sim, D. & Kaminski, J., 2012. Roman Imperial Armour: The Production of Early Imperial Military Armour. Oxford: Oxbow Books