I doubt that 5 billion people could watch the Olympics at all.
Where I am from, there is so little interest in the Olympics that I doubt even half my countries' population would be interested. I have never watched the Olympics ever, and amongst my family and friends, there is little to no mention of it. It is a minor cultural phenomena. This seems to me like there were large extrapolations made.
During the last few decades, for various reasons the interest in several kinds of sports events, including the Olympics, has become much lower than before. Other forms of entertainment that were popular in the past have been similarly affected.
However, when I was a child, a half of century ago, the Olympics was not a minor cultural phenomena, but a really major event in which the majority of the people all over the world would be interested.
How do you even measure that at that scale? I'm sure I would be counted among that 5 billion, yet my "following" was searching medal counts every couple days to see how poorly my country was doing, yet I would never describe it as "important" to me in any way.
I sincerely doubt more than half the population of the entire planet showed more than a passing interest in them, and I'm still curious how it'd be possible to measure that.
Where I am from, there is so little interest in the Olympics that I doubt even half my countries' population would be interested. I have never watched the Olympics ever, and amongst my family and friends, there is little to no mention of it. It is a minor cultural phenomena. This seems to me like there were large extrapolations made.