“The springtails eat the Streptomyces, so the geosmin is attracting them to a valuable food source. And, the springtails distribute the spores, both stuck on their bodies and in their faeces, which are full of viable spores, so the Streptomyces get dispersed. This is analogous to birds eating the fruits of plants. They get food but they also distribute the seeds, which benefits the plants.”
Well, duh!
I live in the desert where it rarely rains and the day after a rain EVERYTHING emerges and the land is full of insects and frogs and toads. Cacti bloom overnight and things you thought were dead come to life.