Perhaps the large ignorance shouldn't be surprising. Circumcision in Sweden has in principle only been performed when medically motivated, regarding the Christian native population.
There have been Jews in Sweden since the 16th century. At first they were very few, but despite the relative increase of their number the last centuries, they only represent 0,2% of the population. There are no figures on how many of the Swedish Jewish men are circumcised, but I guess the great majority are. The Muslim population in Sweden was until few decades ago almost non-existent, but labour and refugee immigration has brought about a number of 2-3% Muslims among the Swedes. Also among these, I expect a great majority of circumcised men.
Thus we can conclude that only a few percent of the male Swedish population are circumcised. Furthermore, most of these few belong to ethnic and/or religious minorities, which are often by the majority population considered "strangers" and not had very much contact with. The majority population simply very seldom sees a circumcised penis, or talk to the owner of one!
Therefor one shouldn't be surprised by the ignorance in circumcision. Though, it's both frustrating and upsetting that the negative or directly hostile attitude to circumcision is so widespread - even among those who usually call themselves enlightened.
Ignorance and prejudice are running rampant. Male circumcision is mixed up with female genital mutilation, which is grotesque. Many think that one can't masturbate without a foreskin. Some seem to think that it's more or less a matter of some kind of castration!
It's also a question of a great deal of self-righteousness and ethnocentrism in the Swedish majority population. "Our" customs are obviously the right ones, those of "the others" are strange, and in addition they are often Muslims, against whom there's a widespread suspiciousness.
Left: The Stockholm synagogue. Right: The Stockholm mosque.
"Can these people really be called Swedes? Doubtful... at least as long as they don't stop this circumcision thing, and start to eat pork and drink themselves pissed every weekend, like civilized people do!"
Ask the circumcised men too! The great majority are proud of and/or satisfied with being circumcised, or at least indifferent to it. There are a few though, who are dissatisfied, and of those almost all have been circumcised without being able to make their own choice. This should be respected and taken seriously. On the other hand, a lot of men in the world are unhappy with their penises regardless of being circumcised or not.
Don't either forget us who have made our own and active choice to become circumcised! Practically all of us have carefully considered our choice during a long time and after thorough research. We know more than most others about the function of a penis in general and a foreskin in particular. We do obviously not want to mutilate our penises or deteriorate our sexual experiences - we want to improve them!