Do people really argue that conscience is so special that the universe refuses to end one?
The universe don't differentiate between a dead human and a living one. From a QM point of view, both body masses, correctly placed, can work as an "observer" to cause waveform collapse.
Also there has been some discussion about how quantum events would only affect the microscopic and the macroscopic would remain the same. This is false, quantum events can only occur in the microscopic, but their effects can propagate to the macroscopic in ways beyond our comprehension. Take the experiment itself, the outcome of a quantum event propagates to the life or death of a human being.
Lastly there have also been remarks about how death needs to be guaranteed because QI only promises consciousness not health or a lack of suffering. I will address that here too. That is a perfectly fine way of viewing QI but there is a distinction we should formalize to make it clear.
Greedy QI and Perfect QI.
Greedy QI just branches from the present moment to whichever consciousness will persist. This can result in a local optimum where you are maimed but alive.
Perfect QI always picks the best branch point of every present moment to account for all future possibilities. I argue this in assumption #2. Once the bullet has say, pierced the brain stem, there is no greedy choice from there that will save you. Perfect QI likely won't maim you as that would limit your survival possibilities. It's the global optimum.
There is still a problem with this though. What if there is more than one timeline where you always live? How is one chosen? My guess would be either it's randomly chosen, or there is only one timeline. Let me elaborate on the latter with a mathematical analogy.
You have an infinite list of real numbers. These numbers represent different timelines, the value being how long you survive. If you order them, you can always find a larger finite number looking at the next one, but none of them are infinite in value. Since QI assumes immortality not longevity we will assume the limit of this ordered list is infinity and not a finite number. Thus there is one reality in which you live infinitely, and that's the limit of this ordered set. The only chance for approaching this limit is through a mechanism like perfect QI.
QI doesn't protect consciousness. Its argument applies to any quantum state, described by any arbitrarily complicated acceptance function of that state. The QI argument implies that you can pick up a rock, and that there exists some set of universes in which that rock will survive indefinitely, exactly as it is now, to any degree of accuracy you care to specify. It's just the more precise your specification gets, the lower the probability mass is.
That's why in my other message, I say QI only promises consciousness. Technically, there are universes in which by sheer quantum chance you are in fact healthy and happy indefinitely. It's just that "a healthy and happy body" is incomprehensibly more orders of magnitude more unlikely than being stuck in whatever constitutes the minimally conscious body. And in fact, the latter isn't a unique construct either. It's actually a function of the selectivity you apply to the acceptance function; you have the universes in which you are conscious enough to realize your plight, but they're dominated by the universes in which you are too minimally conscious to even realize that, which are in turn dominated by the universes in which you are just not conscious. But those are excluded from your consciousness' future states, which means your consciousness is left over with whatever else is left.
The distinctive thing that consciousness adds to the argument is merely that if you metaphorically drew out the future universes in which your consciousness survives, there is something meaningful (to us, anyhow!) "inside" that set. You can do the same thing to the rock as I described above, but there isn't really anything "inside" that set; it's just the rock and nothing else. Excepting of course that vanishing fraction of the universes in which quantum processes drive the rock to become conscious by any definition of your choice, of course.
(Another thing I'd point out is that for this discussion, I have no concern about what your definition of "consciousness" is. The argument works regardless of your definition, it just tweaks the exact non-zero numbers that come out.)
There seems to be a belief that our consciousness will "jump" to an alive alternative. I think that's a strong misconception of what many-worlds interpretation says.
Talking about misconceptions, without having more than superficial background in QM, I doubt that being able to consider even very unlikely outcomes allows you to discard macroscopic causality altogether, which QI basically requires.
I'm not sure you're reading my posts for what they say, rather than what you expect them to say. I think QI is horrible, as in, more suited to horror stories, than something that offers comfort. Nor do I discuss any sort of "jumping".