Not everything in life is an absolute. Fans relate to who they support. Kyle Larson has many more fans in Ca and at dirt tracks because they watched him grow up, he is from there area, age, discipline of racing etc. Danica was relatable to girls and women. Do you follow Ryan Preece in the slightest? Why? You have a photo of an asphalt modified as you avatar. Just an assumption, but there is something in his career that attracted you to him. On top of that he has some success and that just bolsters your interest in him. That's the point. This isn't hard to understand. You can kick and scream and deny it all you want, but look around you. Every sport has become younger and more in tune with demographics because since the dawn of time people gravitate to like minded individuals.
Here is a perfect example. My Son is 8 years old. He has a dirt modified driver that is his favorite at all the local dirt tracks. You know why he picked him to win when he was 4 years old? Because his car was red, my Son's favorite color. The guy wins a lot and that only solidified his opinion of him. Now this guy is like 27 years old. So age isn't a factor, but he rides a dirt bike around the track, my Son love's dirt bikes. The driver is a San Francisco Giants fan, my son is as well. On top of all of these factors the guy treats my kid like family, he takes an interest in all that my son does when we see him in the pits. So yeah, demos make a difference. A demo isn't just age based. It's like minded people with similar back grounds and points of interest.
The point is that to invest into anyone or anything you have to relate. That is why you see younger drivers becoming the norm.