> Do we have better imaginations?

Maybe, humans aren't very different, so it depends whether imagination is informed which seems plausible, or whether it is somehow fixed - modern humans don't have different eyesight than in that period, but almost all of them can read whereas back then almost nobody would have been reading these scrolls.

> Can our sci-fi writers come up with something equivalent that is as dizzyingly far from what we know now, as now is from what Aristocreon knew?

Science Fiction produces things so very different from any conceivable future for us as to certainly be "dizzying" in this sense, Hard "What if?" SF routinely ponders universes where the fundamentals are different e.g. Egan's "Orthogonal" series is set somewhere that the three spatial plus one temporal dimension are laid out differently, the maths works for their arrangement too but gives different results.

In terms of just normal human stuff but more and later, there's loads of that, near futures like Vinge's "Rainbows End" through to some of the distant future stuff Stross wrote.

Also perhaps relevant, Vinge's Marooned in Realtime, bobbles (time bubbles) take the remains of humanity with varying levels of technology and culture 50 million years into the future long after a singularity "extinction event" in the 2200s occurs.

Of course the story is just a murder mystery.

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