Huh? I mean, no, technologically it... definitely wasn't. Remind me how many teraflops the most powerful Roman computer was capable of?
The Romans were plenty advanced, sure, but that's just a nonsense statement.
Bad metric. We could go to the moon in the 70’s, and had supersonic passenger planes, and we could build at scale.
Today California can’t build a train, building a nuclear powerplant takes 20 years and we can’t go to the moon and don’t have supersonic passenger planes. So we have partially regressed despite having more terraflops
If the Roman empire had one thing as advanced as our modern states that wasn't technology per se but the politics, the politicking the perverse incentives to do something to show for and a public whose murmur mattered.
If some city official decided to impress visitors with some smooth roads perhaps he found a solution that wasn't strictly the best economically but perhaps it had other advantages that helped him getting a promotion?
Experience engineers will have retired or found other jobs. Knowledge is gone. The books have been lost, etc. If you haven’t been to the moon for 40 years, then you can’t any more. That’s two generations of people.
Ability is not like a statue that you keep in a museum. Even a car will not start after sitting the garage for 10 years. Organisations and people fall apart even faster.
Modern people had very little idea why you would have a stone stadium until around XX century.