I'm not sure what you mean, I don't think I've seen a single isekai protag try to go back to Earth unless you count the "trapped in VR" ones.
I'm always a little disappointed by how quickly the regular world becomes irrelevant in the story. The intrigue is from how a person from a modern nonmagical culture interacts with a medieval magical culture.
But from the isekais I've seen, I'd say you could replace half of them with a person with amnesia and nothing would change.