yeah ...Iranians love German quality and precision and styling and that includes me ,they are the best for me .
I like everything from their cars ,beers ,sausages ...culture and football ...not so keen on their music and language , I have never heard of this band before and not seeing a guitarist in their just put me off watching ,but as I said it is a novelty for poor Iranian music lovers inside Iran to go and watch them and have a bit of fun.
I grew up with Bavarian culture and I too appreciate German quality, precision, reliability, which like you said includes: cars, beer, food, culture, football(MIA SAN MIA) etc. I grew up with the language, same with Russian so I have a good understanding. BTW Russian is much more of a musical language, like Italian. German, like Japanese is more of a militaristic language . , I am not too keen on modern German music but Bavarian folk is a different story. Same goes with Persian and Russian, not too keen on the modern stuff but sonati Persian and especially Slavic folk, absolutely gorgeous. When it comes to German, even my German buddies I go to watch Bayern Munchen games will speak to me in German and I can answer them. If you ask me to have a full on conversation, then I might bump into problems but I understand the language. Russian is much easier because I have family that I can practice on. German, everyone is back in Europe either Germany or Switzerland. Also, I find that there are tons of similarities between the two cultures Bavarian and Slava, very interesting stuff man. When I was in Iran, the last time in 06 after the world cup, I was blown away at how so many Iranians can speak German fluently I would say next to English, German is a very common language. I also know the song you are referring to, they played it here in the USA as well.
Here are the best German songs of 2016, some are meh others are good. I am just not much of a German, Russian or Persian pop guy.
[video=youtube;DT2PG9EEh_g]https://www.youtube.com/watch?v=DT2PG9EEh_g[/video]