I've been taking Swedish classes for a while now, and it's going pretty well, but I can safely say it hasn't really been necessary to get by in Sweden. It's pretty rude to ask people if they speak English in this part of Sweden, as their English is probably better and more academic (especially in Uppsala/Stockholm) than yours (looking at you, native English speaker that keeps trying to correct everyone).
I will say as a unilingual person (I guess being fluent in British English doesn't really count) it is quite disheartening to encounter situations where my Swedish friend knows the English word/phrase for something and I'm left confused as to how my linguistic mind has failed me. Most of my Swedish friends are trilingual, at least. My roommate, Nina, is fluent in English, Thai, Swedish, and pretty good at Spanish. My other two Swedish roommates are fluent in English and Swedish and studied other languages at school, my friend Michaela that I mentioned earlier can speak Spanish and is also fluent in English, and my roommate that is from Québec, even from the same continent as me, is fluent in French and English and is learning Arabic.
So, why am I reading Swedish, you ask? It's because my heritage is from the two most isolationist Western nations that ever existed, and as such, I am a sad unilingual. Swedish may not be the most useful language to learn, but when you live in Sweden for a year, it is a fun party trick and it's nice to know how to read a menu.
Afterthought: I can speak French at a conversational level. However, after reading Swedish for so long I'm now starting to say "Je måste demander du une fråga."
