Pretty sure I knew (a little) English even before learning it in school. My theory for that has always been subtitles as well. When we learned German in school

Pretty sure I knew (a little) English even before learning it in school. My theory for that has always been subtitles as well. When we learned German in school (which is much more similar to my mother tongue Dutch), I found it very hard. German shows were also subtitled, but there were a lot fewer of them on TV. Side-note: A few years ago, I read about a project for "same language subtitling" (of soap TV series, nonetheless) to improve literacy in India. Don't have a link for that, unfortunately. Your reasoning makes sense, and probably plays a role, but I believe subtitling of English TV plays at least as much of a role. A lot of German TV is dubbed, and the effect of this also carries over to smaller German-speaking countries, like Austria. Now one could argue that this is, according to your reasoning, because they are part of the larger German-speaking community. But that really isn't the case, ask any Austrian, most of them will tell you their mother tongue is Austrian (which is not a written language, but also quite a bit more unique than merely German-with-a-dialect), and "high German" is definitely something they had to learn separately.