Both things can be simultaneously true: the coaches don't have time to focus on all 11 kids and their knowledge as to the particular position may be more limited than the parents & the kids need to hear from one coach and if all 11 parents shout out contradictory information which may not conform to the tactics and vision the coach has set out (e.g. play it long, play it short; pass it, shoot it) it causes chaos. It's one of the major problems we have in American soccer: we are paying all this money and a lot of the education the kids are getting simply isn't good.
There's no good solution to this for the current generation. There is a dearth of soccer knowledge out there even among very highly licensed coaches, and even to the extent there isn't, some of them well just don't know how to teach. European tiered rec overcomes this because the coaches have mostly played the game their entire lives and religiously follow the sport and commentary (which is ubiquitous in Europe). The next generation will have it better. It's also one of the reasons, BTW, why AYSO rec fell apart: too many volunteer coaches who had never played and don't know what they are doing. I've also generally found that the younger coaches out there seem to have a better understanding of the game, though it is not uniformly true.