TDLR; Reject modernity, Embrace Empire!
So for the non history guys wondering why this is a big deal 'we already have concrete?' Yes and it can be stronger than Roman concrete but does not have the longevity of roman concrete as look at the amount of Roman architecture still standing when left untouched by humans for thousands of years.
The cause is it's structure, roman concrete has a lot of lime deposits in it. When over time cracks form, when it rains the water reacts with these lime deposits, recrystalise and fill the cracks, essentially self healing the structure. The romans had nanomachines before they were a thing. Near seawater, their structures actually got tougher over time due to exposure to the minerals in the seawater.
So us finally understanding this means we can now create longer lasting and even stronger structures given time. Lets just hope this Roman concrete is ONLY used in ancient, renaissance or gothic architecture and not any of the shit we make nowadays!
Thought this was a fun example of how much studying history is extremely important to improving the current world.
Pretty sure they did, but modern 'science' thought impurities were mistakes made by cavemen.
They have such disdain for the past that they can't believe the artisans actually spent huge amounts of effort perfecting everything. It was all dirty, lazy people getting lucky. Like how they can't believe humans were sailing the globe 10,000 years ago because everybody was wearing loincloths and killing bison with rocks.