Glad you referenced the Atlanta expansion team from MLS. I was excited to hear they were doing so well, but being from Philadelphia I definitely know that doesn't last a few years into the team's life.
Although I do think as a result of growing concerns of brain injury in football, you may see more parents pushing for their children to not only play soccer as a kid but continue playing it as they grow.
Like any expansion team, Americans just want a good home team to root for. We can only hope more Pulisics come up through the ranks and make the sport and US team watchable. MLS will remain the 5th US sport forever.
Yes, the brain injury issue in football will be very interesting to watch. It's hard to predict yet how that will affect the other sports.