It's a good question that I don't really have an answer for yet. Germans are pretty up front about human sexuality and the body. Saunas for example, are all nude. If you go to the sauna, you're going to be naked while you're there and using the facilities. It's only a body. There are women only days (usually once a week) for those women who may feel uncomfortable being naked around naked men, but on other days, everyone just gets their gear off.
I've heard people discussing circumcision quite openly and not necessarily negatively. It's understood that it's something that's very common in the US, but I've also heard people talk about it for hygiene issues. I don't think it's generally offered as a pediatric/obstetric service in the hospital post birth though, so I guess if people want to have their sons done, they take them somewhere afterward and pay privately. I've read that the rates are quite high by German standards in areas where US military installations are found.
German tv used to have weekly sex magazine shows - hour long programmes that covered the range of topics in sexuality, and these were always quite explicit. While you always saw uncut guys, it would have been unusual to have week go by without also seeing at least one circumcised model. Maybe they did this to include the cut guys in the viewing audience but I don't think so - it's not the way Germans would think.
I've seen quite a few cut cocks in German porn. A lot of them seem to be adult or at least, post infant jobs, but a fair few also look like RIC's.
What I will reiterate though, because it makes me angry to read this whenever an anti gets in front of a keyboard, is that circumcision is far from unknown here. Put it this way. I grew up in Australia in the 80' s/90's with my foreskin. I lost that in my mid 20's. When I'm in the gym or at the sauna here, I feel a lot less unusual/strange/weird/out of the ordinary, than I ever did with my foreskin in Australia.
If the radical right political parties keep presenting it as islamic barbarity, rates may decrease, but reading on German forums, circumcision definitely has a lot of supporters.