Just would like to say that actually the other way happened. Litrpg is a new book genre based on game mechanics. Very dynamic community with lots of amateurs. I would connect it with the pulp fiction movement of the XX century.
Big problem for me with LitRPG I have read, mostly Korean and Chinese is that the system they have wouldn't actually work in games... Game mechanics are there, but they really aren't believable as games would be. In sense that these games would never have the popularity among the average players. Maybe worst tropes is one of the kind hero classes... With massive investment in them. What if one of those players simply quits or gets in accident? All the effort gone?