with the interpretation of LLMs as analogous to a library for the internet (as proposed in Cultural Evolution), it makes it much more useful for society for people to write more
Basically more generally, when the world get's better at processing and routing information, it becomes more beneficial to generate information.
My guess is that something like this happened at the invention of the printing press (as a result of it being easier to spread things), the library (as a result of it being easier to direct things to where they can be useful), the internet (spreading things), and now, LLMs (directing things and processing things)