It’s also heavily dictated by cultural factors. in northern European countries it’s quite normal to know at least English next to your native language. So much so that in finland tourists seem to think that everybody knows English and foreigners who try to learn finnish, tend to complain that Finns switch to English at every opportunity.
Cultural factors are one thing, the other is just that there are only ~5.8 million native Finnish speakers, so a lot of books, movies, music, etc. are not available in the language for purely economic reasons. There are over 90 million German native speakers, and TV shows and movies are dubbed, books translated, etc., so there is less of a need to have high proficiency in English (similar to Spanish-speaking countries).
You'd be surprised, honestly. What matters is also comprehensible input size, so long works like LOTR (which has an excellent Finnish translation by Kersti Juva for anyone looking to find works to read) are a good choice. Similarly, there's a lot of Finnish literature in Finnish which Finnish people spend time reading, some of which is translated to many, many languages. The Egyptian by Mika Waltari is one of those classics. Not nearly everyone here knows English well. TV shows and movies are usually subtitled as well, save for kids' shows. Finland does however have three mandatory languages in the basic schooling, which are your native language, the other native language, and then English. A fourth one is not uncommon either, so we have a lot of German, Spanish, Russian, Japanese etc. speakers here. Hell, jag kan neljää языки.
