Notre Dame could make more money in Big Ten it is a fact. They hate the conference and Michigan for blackballing them in the 1930's.
ND would likely make more money in the ACC because it cause a channel to be formed.
ND doesn't care about money as the end all be all they leave a few million on the table and get to remain independent.
Only way they join a conference is if the Big Ten forces them into the ACC and that makes zero sense and won't happen.
I wonder if this is why the Big is so adamant about the ACC and Big 12 picking who plays in their own championship...ND? They don't want to give an inch and take a chance that the Irish would go all in.