My response here is for the benefit of those parents that will read something like the "personal branding" piece and think that they have yet another responsibility to lay at the feet of their 15-18 year old athlete. And my belief is that creating a personal brand is not at all important to successfully navigating recruiting.
The idea of creating a personal brand is definitely current. But for college sports recruiting, this is over the top advice. Although a personal brand helps market who you are, it will never suffice to market how you play. And in the end, the recruiting process breaks on decisions about whether a recruit's play works for the college program that's doing the recruiting. And they will almost always make that determination after seeing a recruit play.
Player as personal brand might make sense in a highly competitive recruiting environment where the recruiter has a choice of more than one equally talented players. Then things like character and personal mission will supply information on whether one or the other recruit is a "fit" for their program.
And one last anecdotal thing: my son rose to the basic requirements of communicating with coaches, but it didn't come easily or naturally. Adding a layer of responsibility ("hey kid, brand yourself") to the things he was already doing (hitting, lifting, running, throwing, homework) would have blown his mind. Some kids might be able to take that sort of process on, but my guess is that it would draw blank stares from most kids his age.