I guess it depends how you phrase a question about PPLs or Universities as to whether it is really relevant on wannabes (in my opinion). This particular question, I'd agree with you, doesn't seem to fit in with this forum really. However, people might ask other questions like "would a PPL be useful to me when I go for airline sponsorship selection?" or "which University or degree would look best on my CV?", which perhaps would be appropriate here?
Problem I see with banning such topics from this forum is, no matter whether this is the correct place to ask, this is the place you get the best answers. I don't know about the other people on who use pprune, but I only really read the wannabes forum, and occasionally look at a couple of others. Probably a fairly large number of people who read wannabes are people who have recently been through university / currently at uni / just about to go, and a fairly large number of people have probably fairly recently done PPLs, just doing them. Therefore you're going to get the best answers to these questions on here.
I agree though that you do have to limit the amount of subjects that can be discussed on here, afterall, we're reading this to find out about subjects that interest us - that's why I read wannabes rather than other forums, and we don't want to have to look through a load of irrelevant messages to find the relevant ones.
By the way, I'm thinking of buying a new car soon, which model do you think would make the best impression when turning up for my next sponsorship interview?