Finns don't really learn swedish, unless one lives in an area with a large swedish speaking population. In total swedish speaking population is only a few percent, but there are areas with a higher concentration. The reason it's bilingual is because swedish is the second official language in finland. Because history (sweden ruled finland up to 19th century, swedish speaking population retained considerable political power even after that).
To retain a language it requires active usage. Swedish has zero utility outside school environment unless someones life is such it includes interaction in swedish. Most people I know are more fluent in english than in swedish. While I personally retain some rudimentary basics, when I need to talk to my swedish colleague, I use english.
To get MSc one must theoretically prove to be able to communicate in swedish but the minimum acceptable level - how to put it - is not very high.
