One thing I will point out, outside of the US, "Andretti" doesn't have the same impact. Mario raced a handful of seasons, and won one championship. Never won LeMans. All of Mario's wins in the US were pre-internet, so few ever knew of how important they were. And Mike was pretty much a washout in F1. Most of his Indycar wins also came prior to the internet, so not much international exposure.
Andretti has as much cache as Phil Hill- who won one championship. And arguably vs Gurney who won a race with his own car.
Look at it a different way- outside of the F1 circles, how big is Senna or Schumacher? I remember the day Senna crashed, I went to an autocross, and the guy I was corner working with had never even heard of Senna. Schumi loved to come to the US as so few people knew who he was.
But it also very much seems that Mike rubbed people the wrong way, pretty badly.
And all of that ignores the lack of success over the last decade of Andretti Global.