My name is Nova and I am a goddess created in this modern era, on this iteration of Earth, because of the planet's completely rational paranoia of isekai protagonists. The world had finally had enough of stories like Doctor Who, Worm, and various isekais where either the fabric of reality, the time continuity, or barriers between dimensions were broken, twisted, or bypassed.
From my home on the moon, I maintain a barrier around Earth that prevents the approach of aliens, dimensional travel/manipulation, extra-dimensional travel/manipulation, temporal travel/manipulation, manipulation of fate, Cthulhu and its spawn, and other things that don't belong; along with preventing souls from leaving to other realities. This meant no hero-summoning could take from this iteration of earth, no isekai protagonists could either transmigrate away or return with world-breaking powers. No entities or endbringers or Doormaster or Khepri, no hostile Otsutsuki, no Hajime Nagumo and his guns comparable to bombs, no magic spells with nuke-like explosions, and no lovecraftian nightmares.
Occasionally I could be convinced to part with a soul in my jurisdiction, but I had rules. The only souls I would allow to be taken were souls that had a trait or quality that required their use; if any old soul would do, I'd send them off to a different/alternate earth. Additionally, even if they met my first requirement, the second was that they had no qualms about leaving behind this earth forever. Meaning that the candidate had to have no desire to return. Lastly, the only way for these divinities of isekai to get a soul under my responsibility was to wait to receive it from me. No truck-kuns, no kidnappings, no premature deaths, no manipulation of fate, no sneaking by me. The deities in need of human souls would have to wait for the human's life to naturally expire before I, and no one else, would gather the souls and give them to the entreating Godly beings.
This system was wildly unpopular but it worked and had so few loopholes that I refused to change a thing about it.