In my vision having a gap before starting university is not a waste of time but I think its not good at the same time.
At first, if you start working after college you would have more time to learn how to do the job and improve your skills. Another advantage for taking a gap before university is you can travel around the world and gain some life experiences which would help you a lot, maybe more than lessons which you can learn on university.
But decisions in our life have some disadvantages, and about this subject I think the most important one is without being educated you should be an expert if you want to get hired somewhere, its because people trust you harder. It is true that people care a lot about the job experience which you have but primary education is necessary at the same time.
In conclusion, being educated and having a job experience are both important, and in my opinion the best way is to have them both and it is possible, because you can do a part-time job while studying in university and after 4 years of studying instead of learning more skills you have a little job experience and you can find a better job than a person who didn’t finish the university.