If there's one hard lesson of history I keep relearning, it's that almost nothing ever happens until it materially is required to happen. Language and agriculture waited until population density was high enough. The industrial revolution didn't happen until the logistics and population sizes again necessitated massive changes, even though the steam engine was hundreds of years old. Revolutions don't happen until the population is starving.

If anything in history is impressive it's the rare individuals and societies that change before they're forced to by material necessity (and those cases are often debatable). Really dampens the notion of idealism being viable.