And something like 90% of the world population was born during her reign.

Nope, more like 98% of the world population.

No, that's not how it reads at all. It clearly implies that they were born during the period in which she reigned.

The crazy thing is that we not ever see 10 billion at this rate. Globally we are down to 2.1 births per woman, and the majority of nations now have a birth rate below 2, meaning most countries are below replacement. And even the positive birth rate countries are rapidly trending downwards (with the exceptions of Uzbekistan, Kahzakstan, and Iran).

It will be very interesting to see how the population J curve flatlining affects global society. We live in interesting times.

Follow up: I was curious about the math, so I thought others might find these numbers interesting as well:

At current continual growth rates (assuming the decline comes to a dead stop and remains steady), we will see 10 billion people late 2044.

If the decline of the last 10 years continues indefinitely, humanity would go extinct around 3913.

She started with Winston Churchill and ended with Liz Truss.