Multiple highly regarded venues with well-known drivers, strong fan support, familiar vehicles, and ties to patriotism.
Indy TV needs more input from pit reporters, spotters, .... notably interviews from engineers and owners. Al so maybe change format like nascar on first driver a lap down to regain the lap with " the lucky dog".
Viewers want to see their favorite driver in the mix. Otherwise they'll change the channel.
Though perceived by many as unfair, it works. Viewers are definitely watching by the end of the race!!
They like aggressive driving