I also don't believe that there is any future point where all or even "almost all" of the best HS players will choose to go the prep route... Unless the high schools were to start dropping sports altogether due to expenses such as equipment, field & gym maintenance insurance, and legal risks etc. becoming too great (VERY unlikely, but not 100% impossible).
However, some of these prep programs will prove to be well-run and otherwise a solid option for kids (and their parents) will rise to the top while the less well-run programs die. Places like Montverde and Oak Hill have shown the model is certainly workable, and a strong choice for many or most of the kids who played for those teams.
Of course, mileage may vary... I've heard it's darned expensive to go to one of these prep deals, so that and the fact folks want the best for their kids means research... LOTS of research should be done by the parents considering sending a kid to a prep academy.
From all I've seen, read, and heard, Prolific seems to be run really well and does everything it can to provide its kids with educational well-being as well as a terrific opportunity to get the most out of their basketball abilities. Educationally, all its players go to Justin-Siena HS and it's been reported that their classroom performance has been excellent.