I think as an entire system, you're probably right. But a kid that plays for a good school ball program, and a good AAU program, is getting really, really good preparation for college and beyond.
I can't stress enough how important and beneficial I think the differing styles and types of games school ball and AAU ball can provide. Depending on the program a kid might come up through in Europe, he might play the exact same system from age 13 to age 18. And if that system doesn't jive well with American college ball, then that kid is at a huge disadvantage to his American counterparts coming in to college.
As with everything, times are changing too. I played with and against a decent amount of European players back when I played. To a man, they were all well behind the American players in their ability to defend, and with how they handled physical play. That gap is obviously closing. But its not completely closed, in my opinion. Most of the recent natty winners have been led by American kids, that came up through the school/AAU programs. Arizona, Gonzaga, Creighton...St Marys...teams that have a higher percentage of foreign players...they have really good programs going. But they nearly always end up losing to a more physical, more athletic, team that's led by a bunch of "dudes" that came up through the AAU system.