Apparently Charles is now DofE and the decision about what to do with the title when he becomes king hasn't been sorted yet. Edward was originally in the running then it was changed.
Don't know why but all these spare dukedoms must be a real headache
Maybe the Queen thought it best to wait to see what was taken back from Andrew before dishing them out again?! If you're organising a household budget, you look at all the available income before assigning your spending, so that's probably the royal version!
On the surface of it, it does seem like general knowledge is lacking among the younger generation of adults, BUT I think this is only a small part of the story. When people my age (mid 40s) were growing up, there were some topics (like the RF) that were considered 'central' common knowledge and then a relatively small sphere of wider knowledge that would cross your path, depending on a few relatively static circumstances such as your family, background, hometown etc. Most of the other stuff would have to be specifically sought out and searched for (often in vain); realistically, I wouldn't have cared to bother thinking about 99.999r% of it.
The internet has now just completely blown the concept of general knowledge out of the water. When I was 18, I not only wouldn't have known, say, who my local borough councillors were, but I also wouldn't have known an easy way of finding out their names. Maybe take a trip to the council offices when I next had an opportunity and then try to wade through several of the departments there, to find somebody who could verify the official list.
Contrast that with today, where, earlier on (when he was awake) - a Sunday evening - I could have asked my 9yo DS the name, birthdate and spouse's name of the President of Timor l'Este, and he could have found it out - and far more associated info besides - in 5 seconds. In fact, I've just done that, and found the answers.... and now I've forgotten again. Not only is there a billion-fold the amount of information out there - so in no way cut and dried as to which minuscule sections of it you would consider essential - but there's no need whatsoever to retain most of it in your head anymore, because it's all right there instantly whenever and whatever you want/need to know.