This particular article argued that having a successful athletic program does not necessarily "market" a university as much as some may think. Not that it doesn't or can't, it just isn't a given.
The same applies to your point. Rutgers developing a (relatively) successful football program from the ashes some years ago almost certainly increased athletic donations. But once you get a "hit" I think it might be difficult to replicate. Success in the B1G, whenever that happens, probably won't materially increase gifts.
Two factors that I don't think universities are good at realizing - funds for most donors are not unlimited, and it is perfectly ok to challenge for an increase, but to expect a huge increase every year is just unrealistic. I remember RU suggesting I more than double my gift one time, I was shocked. I increase my gift (now, to Arizona, with a set amount to RU WBB) slightly each year, as I am able. Substantially, no way. The 2nd factor is that I can give to athletics or academics, but the total amount isn't going to change. I currently give to athletics, although I would consider academics at my alma mater, Rutgers. At Arizona, I'll likely only give to athletics.