Just out of curiosity, are you hard at hearing AgX or do you just not understand? You seem to express yourself so fluently ("seem" since this is also a second language to me), I find it hard to believe that you wouldn't understand.
Has the German tradition of incessantly dubbing
everything really impaired the German peoples ability to understand spoken foreign languages that much‽

I could imagine Scott being a mouthful in that case, but the interviewees are mostly very articulate and careful in their pronunciation.
Well, quite often I have difficulties in understanding even what I read here at Apug... when fellows get colloquial. And I myself have been blamed to have a strong german "accent" in my English writing here. But still I am writing in 3 languages daily. And I understand quite some dialects of continental germanic languages.
I had 9 years of English education at school, what in West-Germany back than was anything than practical for life. The same time I listened to British radio half of the day. But understanding spoken English, especially American English by speakers who do not care, still can be an endeavour for me.
I have no problem at all to understand our fellow Greg Davids , but the introductory speech of Scott Shephard already is a nightmare...
Yes, you made a good point:
The availability of dubbed tv and cinema movies or rather the sheer unavailability of the original versions spoiled my generation. (Though there still was radio, but only few listened to foreign radio.)
Books in English, especially textbooks, were extremely hard to get by, as books on the most rare topics were available in German. (In contrast to e.g. the Netherlands or Flanders)
Surprisingly young germans speak an outstanding English, many with an american accent.