I wasn't at University, but met my DH age 18, we broke up, got back together and married at age 27. So I deserve a nickname??
I can't find the article now, but will keep searching, that described how it was Catherine who wanted to wait for an engagement, to be sure she could handle it, William had decided to marry her and wanted to announce, she was more cautious. But that doesn't fit the press narrative, or that of Upper Class who looked down on Catherine and didn't think she was suitable.
As to a previous comment about Harry being thrown under the bus to protect William. It doesn't quite work that way, and that part of Tom Bowers book is one of the weakest - he has very few sources to back up those particular claims.
I'm sure William also drank and partied, drugs may have been involved. He was pictured falling out of clubs and drunk in taxis. Unlike Harry - he wasn't pictured punching journalists or his Security, wearing a swaztika or partying with hookers in Vegas.
Royal Press doesn't quite work the way Hollywood press does. If they have a juicy story on the Heir and are offered another story on a lower Royal to print instead - they now have 3 stories. The one about the Heir, the one about the other Royal and also the one about the attempted cover up. The RF aren't Hollywood - they can't really limit Press access - they need it to publicise their jobs. If the Press had proof William had been behaving in the way Harry was with drink and drugs - they wouldn't have held back. It would have fed into the Bad Charles/Bad Father compared to Saint Diana narrative they were caught up with.