Education, writing, and materials would be independent of agriculture or any one local invention.
It often takes an incredible number of different materials fabricated in uncountable ways for generations before even one single new material can be identified or developed.
Same with inventions.
Each culture that responds to their environment sustainably for millennia is not in a rut compared to those who truly got stuck in some unsustainable way and are no longer with us.
Intercommunication between these different environments can combine the accumulations of education, writing, materials, and inventions, and they can be seen to grow in an exponential way, so it appears those millennia were just the low-slope early part of the same curve.
It often takes an incredible number of different materials fabricated in uncountable ways for generations before even one single new material can be identified or developed.
Same with inventions.
Each culture that responds to their environment sustainably for millennia is not in a rut compared to those who truly got stuck in some unsustainable way and are no longer with us.
Intercommunication between these different environments can combine the accumulations of education, writing, materials, and inventions, and they can be seen to grow in an exponential way, so it appears those millennia were just the low-slope early part of the same curve.