You do have a point.
Look how much light has been shown on concussions and the major impacts they have on people. Even cheerleaders are having issues, due to falls and concussions.
I know a lot of parents that were pretty major football players and are football fans, but dont want to let their kids play football because of the injuries and concussions.
One would think things will need to advance significantly in safety or there MAY be a decline in the sport, including helmet design, rules, etc. But then again the sport continues to be hugely popular, and it might take longer for a major shift to happen. But look at the shifts in other sports over the last 20-30 years, NASCAR, MLB, NBA have all seen significant declines. NFL has been up and down.
Honestly though 30 years, a lot can happen. We could have established colonies on the Moon and Mars by then. We could be in the aftermath of WW3 by then. Think of where the world was in the early 90s vs today, think of technology, cellphones, computers, internet, etc. Its crazy to think.