I'm deeply involved in elite youth basketball at middle, high school and college level, plus I take care of skills development for kids ranging from 6th grade to college level besides that and I see different.
It's true though that yougsters don't have eyes for Jordans yearly sig model only but it's up there, that's perfectly fine and that goes with the fact that there are several other great and inspiring products offered these days that are associated with other athletes that represent the current gen of young athletes in some different ways as well. I'd say peoples needs and values have broaden with time and the Kobes, Lebrons and others have different things to offer to the younger generations and it's positive in the end.
Historically, in the 80's and early 90's at some point Nike had only Michael with his name on a shoe. They were hesitant to even put another player's number(only) on a shoe, then they slowly started to incorporate other players initials and personalized logos on shoes with Barkley CB34 and the CW4 and etc... but they were signature line shoes only(much line PE's) but NOT true signature shoes per se. Around the same period came the other true ''full'' signature shoes from other companies the Shaq's and I3 from Reebok, Cons with LJ, LA Gear with Malone, etc. Nike then multiplied the signature lines with Zo, Jason Kidd, Nash, Garnett, Pip, etc and a few years later the Kobe's and Lebron's eras amongst others.
Point is even back then in the mid 90's, there were kids looking fwd to other shoes and sources of inspiration besides Jordan. It's always been like that and today is no different, it's just that the other players names have changed over time, more signature shoes available not only from Nike and Jordan is still at the top of the food chain, so lets not forget our history here and lets not lose sight of the broader picture either.
At 200$ retail when you got kids growing up and outgrowing shoes every 3-6 months, I can understand parents pushing their younger kids towards a 140$ Ja shoe or JT, Zion or whatever other option as well, so it's no different to me than the 90's when Nike introduced the signature line in the end, just a more evolved way to market the products. Lastly lets not underestimate the Impact Kobe, Lebron or others might have on their respective generations. The pie has certainly gotten bigger with time but it can only be shared and seperated a finite number of ways, i.e. there is a limit when it comes to market share. That's how I see it but that takes absolutely nothing from Jordan or the Air Jordan line, but rather the opposite since they are still super relevant to this day and always will be IMO.