People's desire and ability to speak English vary greatly depending on their social class, native language, employment sector, age, etc. Excluding the people who happen to have poor English is very undemocratic.
...and then there's immigrants. If someone moves to Sweden, do they have to learn Swedish? English? or both? And people with learning difficulties, do they also have to learn English in addition to their native language?
I'm a big fan of multilingualism, but governments can't require it.