As a part time pub quiz creator, I don’t really think those results are all that horrible - the problem is the questions. You call them ‘simple’ and superficially they are, but the problem - for me - is that they are binary (in that you’ll get the answer completely right or completely wrong) and they require specific, detailed knowledge.
The EU currently has 28 states? Fucked if I know - I think it’s the same as the number of stars on the flag, but there’s too many there to remember. If I really wanted to know I’ll check Wikipedia, but generally it’s irrelevant information.
The second one I’ll give you - that is the kind of thing that I agree people should be at least aware of, even if they chose not to vote, and/or don’t understand the specific voting mechanism being used (FPP? MMP? Fuck nose.)
Switzerland? I think I know the answer, but really, who the fuck ears? Does it matter whether they are or not? No, not really. I don’t know, and suspect they probably aren’t, given their famous stance on neutrality. But knowing whether they are or aren’t doesn’t seem to obviously link to any deep understanding of the EU.
As a side note (and, I realise, somewhat contradicting the point I make above), I suspect if you ordered those countries by date of joining the EU, and again by size of country, then you’d would see a strong correlation between those factors and ‘knowledge’ of the EU as expressed in the questions. In other words - recent joiners are likely to have recently been subject to a sustained propaganda campaign, and be aware of these things. Similarly, citizens of small countries tend to be hyper aware of their place in the world, and more likely to maintain this kind of knowledge.