> The inclusion of a reinforcement material: Roman concrete was often reinforced with a material such as iron or lead, which helped to increase its structural strength and resist cracking.

Sounds like chatgpt messed up it's facts? If this means reenforced like with rebar, the Romans didn't do that - and that's part of why their concrete structures lasted so long - when designed to be under compression rather than tension (arches, domes, etc)