>>283627719
written by someone who hasn't watched Heaven's Lost Property
I'm not being too serious I just wanted an excuse to post Nymph

If there was a show where the MC got "isekaied" to save a different world but failed and the world was destroyed but he miraculously came back to earth, is that an isekai?
The point of isekai, before all the slop, was to imagine how people would react to being thrust in certain situations and the effects on said person. The world wasn't the point, it's effect on the people are.
In many isekai, the MC can never go back to the OG world. Does that mean that world doesn't matter? That would be like saying the past doesn't matter because it's not currently existing. The effects of the past are very real and continue in people (whether they can overcome them ect)

I haven't seen ".hack//"
from that MC's perspective, it sounds like it can be considered one