Calling someone who served 10 years in the British Army, including two tours of Afghanistan, a “loser with no achievements” says considerably more about your judgement than it does about Prince Harry. To dismiss a decade of military service, including deployment to an active war zone, as though it amounts to nothing is breathtakingly ignorant.
Harry chose to leave the Army after ten years. Further progression would have involved increasingly desk-based responsibilities, a direction he recognised wasn't suited to him. Knowing your strengths and choosing a different path isn't failure.
He subsequently went on to establish the Invictus Games, an international sporting event for wounded, injured and sick service personnel and veterans. Whatever your opinion of Harry, that is an achievement in its own right.
There's also a rather unpleasant layer of intellectual snobbery running through your comment. Not everyone is academically inclined, nor should they have to be. Some people excel academically, others are technically gifted, practically minded or thrive in entirely different environments. Why are we still perpetuating this ridiculous notion that university qualifications are the ultimate measure of intelligence or achievement?
I'm sure Prince Carl Philip's qualifications and career are perfectly respectable, but using his graphic design credentials to belittle someone else's decade of military service is a particularly bizarre comparison.
Perhaps you'd like to undertake two tours of Afghanistan yourself, serve your country for a decade, and then have someone sitting comfortably behind a keyboard dismiss you as a loser who has achieved nothing. I wonder how you'd feel about that?
You don't have to admire Harry to acknowledge his achievements. And frankly, an education is supposed to broaden your mind, not give you an excuse to look down on people whose achievements happen to be different from yours.