Well guys, as far as it being "already there", The vast majority of HS age top college (and pro) prospects are still playing HS ball. Also, on average, more and more HS baseball players are playing near year 'round, getting private instruction and doing strength training/speed& agility work. Sure, you can still find plenty of bad HS baseball but the world is more visible now.
As of this point in time, the best players still play HS ball and the good players are generally better and more developed than they ever have been. Could it shift more toward a travel alternative during HS season in the future? Sure. Do we know that the current recruiting environment is based more on travel? Sure. But we are not "already there" and keep in mind that most baseball fields in existence today are school property.