While I agree with you that Germany doesn't have the intellectual prowess it once may have had, I don't think you can consider the Nobel prize a valid metric, personally. The Nobel prize has subverted itself many times over.
While German academia was rebuilding itself, American academia was chasing clout - one side effect being that the Nobel prize is more of a carnival attraction than an academic accomplishment.
Prior to Nazism, Germans would collect as many science Nobel Prizes as the British, the French and the Americans together.
https://preview.redd.it/nobel-prizes-by-country-manually-upd...