I found dubbed shows significantly easier to listen then native shows. It is actually easier to learn from those then from native shows. Dubbing is almost always better pronounced and less mixed with background sounds.
Also, the claim that it is impossible to learn if you don't have perfect cc subtitle in target language is absurd. You can use subtitles in own language to get the meaning.
Also, the claim that it is impossible to learn if you don't have perfect cc subtitle in target language is absurd. You can use subtitles in own language to get the meaning.