I doubt that the average native English speaker would pass a C2 level exam (even if you only consider the US and UK, as there are many other countries that spea

I doubt that the average native English speaker would pass a C2 level exam (even if you only consider the US and UK, as there are many other countries that speak English (for example India). While they probably won't have any problems with the grammar, C2 uses a lot of vocabularity that you won't be familiar with if you don't read much.