Just for some context, in Chainsaw Man part 2, Pochita ends up erasing the concept of death (why people don't make bots about that?Pochita eating devils and erasing concepts) which causes the entire balance of things to go itself, because without death, now people suffer for eternity, which rises the fear of devils, but the thing is, INSECTS benefit the most out of this, because they reproduce faster, and they eat people alive, this makes the insect devils so strong, that they surpass even the primal fears.