To answer (2), your utility function can have more than one reason to value people not dying. For example, You could have one component of utility for the total number of people alive, and another for the fraction of people who lead good lives. Since having their lives terminated decreases the quality of life, killing those people would make a difference to the average quality of life across the multiverse, if the multiverse is finite.
If the multiverse is infinite, then something like “caring about people close to you” is required for consequentialism to work.
To answer (2), your utility function can have more than one reason to value people not dying. For example, You could have one component of utility for the total number of people alive, and another for the fraction of people who lead good lives. Since having their lives terminated decreases the quality of life, killing those people would make a difference to the average quality of life across the multiverse, if the multiverse is finite.
If the multiverse is infinite, then something like “caring about people close to you” is required for consequentialism to work.
Actually I think I’ll take that back. It depends on exactly how things play out.