In actual fact the UK currently has around 4000 professional footballers, many of whom will play for a couple of years before moving on, and some of whom will play for a couple of decades.
The UK currently has 14,000 professors the vast majority of whom will fight tooth and claw to hang on to those positions for a lifetime.
So there are more professors than footballers at any one time, but due to football's higher turnover, and shorter tenure, many more people will be a footballer than a professor over the course of their career.
The bottom line is that professional football is actually a relatively attainable goal for young British men, and should probably be more encouraged as a realistic career option.
...and when you do put in your application to Oxford, Cambridge, Google, or Facebook, your long-gone 3 year stint as a utility midfielder at Dundee United is only going to make it more interesting.