I think marina summed it up succinctly: University is no longer an advantage to have; it is a disadvantage not to have.
Many employers don't even care what your 2:1 is in now, so as long as you have one. I definitely would have agreed with you before 16/17 since my folks are old-fashioned and went on long and loudly about how they didn't need to go to uni.
I can only talk as an average Joe with real world experience. Basically, I applied for jobs at 16 (some time ago) and the same mantra was relayed back to me: need experience to get experience. I had over 5 A-C grades, as they usually specify that to be the minimum, so that wasn't the issue. Now, my folks are from a different time, and back in their day you could have just left school, got a job and - the key thing here - train on the job. After years of retail, I finally felt like I had to jump on the bandwagon and go to uni. I haven't finished uni yet, but hopefully it will finally be enough to get me where I want to go (not giving away the degree subject or uni - I think it might be in the top 50. At least, it definitely was at one point).
Maybe my situation was unfortunate, or I was somehow lacking in something that would have excelled me, but that's what happened and I feel although what you propose makes sense, it kind of comes across as boom, bang, job done.