These are excellent points.
Racer interaction with fans has always been key. In NASCAR, its part of a driver's job automatically as are sponsor hospitality interactions- makes the whole game more fun for everyone. There are plenty of folks in many sports who understand that signing autographs for hours, as tiring as it might be, is what makes their endorsement career $ possible.
I've got a friend who for various reasons got invited to Ferrari's hospitality gigs at a few F-1 races (as a guest and not even in the US!) - lavish and up close and personal with all members of their team from managers to drivers to pit crew. Followed by race action seen from the private Ferrari boxes so one can root for the guys you just met. Guess who he follows these days?
I remember casually meeting Gary Nixon a couple times at local bike shops near Baltimore when I was just learning to ride in the 1960s- followed his career with interest. (The Triumph importer was in Timonium and tested bikes on a nearby road and undeveloped land there). Disappointed by his too young death a while ago..
No doubt internet fan interactions are becoming more important and far more possible with the proliferation of smartphones. Racing series that adapt can be predicted to garner additional fans for doing so..
In Supercross, note the mingling of the crowd with the teams in between heats. Even in Monster Truck the drivers go out of the way to play to their fans- running vehicles right into and beyond the point of destruction, sometimes even on their side, knowing full well that it will take extra repair $ and crew time to fix the damage. The two leaders of the Senior TT at Isle of Mann give great, thoughtful interviews though not as polished as some others. Grumpy non social bike racers are and will continue to be a thing of the past- if for no other reason that virtually all modern racing rapidly becomes a team sport aas one progresses- loners, no matter their talent, will be limited..