This doesn't seem to add up to me.

First, the future doesn't appear to be set in stone, and treating statistics like it's a spawn chance against every slot that might exist doesn't work. There may be a quadrillion people in 5000 years, or there may be zero. You can't roll dice against schroedinger's humans, at least not with this kind of intuitive math.

Second, demographers estimate 109 billion people have lived and died in the past 192,000 years. While you have a higher chance of being born in this period over any singular, specific period prior, the vast majority of human lives exist in the bulk who are already gone.

Put another way, there's more people than ever right now, but if you had even odds of being born at any time in human history up till now, there's a 92.7% chance you'd already be dead in 2023.

The only thing worrying about that is that the time period that supports the most humans isn't in the future, when we expand into the stars.