Golf was in a bit of a stagnant stage between 2010-2013 and it was still a more "experienced" man's game (and even a few year before that). Luke Donald was #1 in the world for 56 weeks (remember that?). Lee Westwood, Martin Kaymer, Adam Scott, and a recovering Tiger (in 2012-2013) were #1 in that stage. Phil hung around. Rory certainly was near the top as well. But for the most part that was an "Experienced" player era. Golfers hit their peak around 30-35.
That changed with the Big 3 that emerged in 2015 when many thought a new "Big 3" was forming, including me -- Rory, Jordan Speith, and Jason Day. They had been dominating the recent majors and were all less than 30. Youth had not dominated like this in recent years.
And now fr the most part these guys have been replaced - since those 3 there has been runs by the following at #1 -- Dustin Johnson, Jon Rahm, Justin Thomas, Brooks Koepka, Scottie Scheffler.
Just think of the rookie class that started in the summer of 2019 -- Hovland, Morikawa... I think Scheffler was the year before that
Golfers are hitting their peak at such an early age -- creates ridiculous depth. Its hard to stay on top for any prolonged period -- you will just be replaced by the next hot golfer who has things figured out that year. The #1 spot I think will just be recycled by quite a few over the next handful of years.
That being said Scheffler has opened a decent sized lead (more than one victory). If he continues to play well this summer even without victories he could have a fairly long run (for these days) at world #1.