According to Cowen and Grier, the end would more likely come from economic pressure rather than any kind of government regulation. Insurance companies would simply stop writing coverage for first high school and then college programs if medical science proves a linkage between normal football play and significant brain damage. Before that, the cost of such coverage would force smaller colleges and most school districts out of the market, unable to afford increasingly high premiums.
It's certainly food for thought. The idea that football is too big for that kind of thing to happen, they point out, is not supported by history. The first half of the 20th century featured the marquee sports of baseball, boxing and horse racing, and only one of three has maintained anything like its former status.
Read the article for a fuller explanation of the possible endgame for football, as well as some of the economic impact that kind of passing might have.