If the ‘afterlife’ is infinite, then it will have infinitely more integral measure than the normal life.

Infinite as in "if you succeeded to make it into situation X, you are guaranteed to live forever" or merely potentially infinite, as in "for every situation X where you are alive, in some Everett branch will survive it" (in other words, you never run out of quantum immortality)? In the latter version, the integral of the 'afterlife' may still be smaller than the integral of 'normal life'.