^
In 2012, 6/10 entries in the top. 10 were in native language or partly in native language.
In many European markets English is not even the second or third most known language, so people exaggerate when it comes to English I'd say. ESC is not really a lyrical contest and never were and English just happens to fit the 'simple to the ear' melodies as it flows well and although not all understand it they recognize the sound of it, but that's because they've been constantly bombarded with music in English through cultural imperialism, English is considered 'cool' although many don't even understand simple phrases.
When the argument that choosing English makes 'more people understand the lyrics' comes up, I'd say people mistake themselves. The general viewer in Russia, Ukraine, Turkey, Spain, Italy, France, Azerbaijan etc. doesn't know English that well or at all to begin with, and again it's not as if the simplistic naive lyrics we get in English really is much worthy of 'understanding' anyways, so the whole argument that choosing English for the lyrics is simply misguided.
Music is universal though. A good song will translate a feeling without the need to understand the lyrics, and the language itself is a tool not to be overlooked. Songs do sound differently in different languages and that should be regarded as a strength because the linguistic characteristics also add these special flavors to the songs. I mean some songs just falls flat when translated into English. People think 'it's just a language', but it's not... the different languages adds structures that makes the songs unique aswell.