I suggest to leave it up to the other persons to decide whether they are benefitted. For example: I have a happy, positive life, so I claim that my parents benefitted me when they caused my existence. So there does exist someone (me, now, in this situation) who claims to be benefitted by the choice of someone else (my parents 38 years ago), even if in the counterfactual I do not exist. So my parents made a choice for a situation where there is a bit more benefit added to the total benefit. If you disagree in the sense that you don't think you were benefitted by your parents when they chose for your existence (even when you are as happy as I am), then that means your parents did not create an extra bit if benefit and you were not benefitted. More on this here: https://stijnbruers.wordpress.com/2018/02/24/variable-critical-level-utilitarianism-as-the-solution-to-population-ethics/