Early in their careers, even exceptional people face obstacles from gate-keepers. It wouldn't surprise me at all if there have been Germans of similar temperament, credentials and talent as Carmack or Luckey but who struggled much longer to stand out to a sufficient degree that they could get great job opportunities or funding in a that much more credentialist environment.

I like to imagine that such people would have found a way to emigrate and make their impact abroad. Either way, the cost to Germany itself (and Europe generally) has been immense.