Don't those 99 enjoy being alive despite all of the things that would have killed some of them had they not taken the vaccine? If "some" is at least 1%, that sounds like an individual benefit to me.

If you take the vaccine, you have a lower chance of dying over those 4 years. You also have an infinitely higher chance (specifically 1% vs 0%) of dying from the vaccine, but that doesn't change the previous sentence.