The important word in my analogy was "invent." Given that the technology exists, lots of other things would happen—an emulation could be plugged into arbitrary "sensory" inputs, so a simulated universe could be created for it; that simulated universe would seem like an inviting prospect for those that do not wish to continue a life that mostly consists of sitting around on the Internet anyway, so more people (first-adopters) would upload as well, even if their "real" bodies continued separately; the large number of ems would provoke discussions of em rights, which would lead to internationally-funded medical programs to create two-way bridges between our reality and the simulations... and so on.
That's what I mean by "discontinuity": you can't give a cost-benefit analysis to something like a trillion dollars, because one trillion-dollar investment can completely alter the course of civilization with its knock-on effects.
Well, you're making decisions about someone else's mortality. Maybe they wouldn't want to live forever with everyone else that they knew dying? Maybe they would want to have a physical existence in the form of a human body. You're denying them that.
I think the parent's phrase "sufficient technology" was meant to be interpreted as more than my "brain uploading and emulation"—i.e. an infinite Matrix landscape, synchronized with a doorway in the real world, that would gradually quantum-de-/re-materialize them as they progressed further into or out of it, so that, on the outside of the door, they were real people made of real matter, but ten or fifteen feet inside they were completely virtual. Assuming a wide-enough door, you could bring in your house, your car, whatever else you'd like, and bring them out again if you wanted to live a mortal life. (But, if you got your leg blown off in reality, you could always go in and, sufficiently digitized, apply a patch from a record of your previous body and walk back out, good as new.)
The problem with speculative fiction is that it needs a technological conflict. Worthwhile utopias don't do that.
The rest of the word might hesitate to consider the person "not dead" when their body, their instantly recognizable human feature, has been taken away from them.
That's what I mean by "discontinuity": you can't give a cost-benefit analysis to something like a trillion dollars, because one trillion-dollar investment can completely alter the course of civilization with its knock-on effects.