You went wrong because you now have a degree that does not accurately reflect your college experience. You did not learn the material you were intended to learn; you did not learn the discipline that is required to do your own work when it may not be something that is “fun” or “interesting” for you; and you did not develop the moral integrity that would require you to follow the university’s rules, rather than to simply “not find fault” with them.
Extrapolating to the real world – first of all, your degree now implies that you do have a core understanding of science and math which you do not have. You are a very poor representative of your university, and any future employer may expect things of you which you are unable to give.
Second, your degree from a prestigious Ivy League School with a strict core curriculum implies that if you are assigned tasks, even if they aren’t specifically to your liking or directly in your field, you will be willing and able to complete them. Whatever you seek to accomplish in life, not all of it is going to be fun. Being a successful writer requires doing publicity and promotion for example. Depending on your field, it may require occasionally writing about subjects that don’t interest you, or doing dull, boring research so that what you end up writing is accurate. Part of the discipline of core curriculum is teaching people how to do the stuff that they don’t like, as well as the stuff they do like.
Finally, obtaining a degree from a prestigious Ivy League School implies a certain amount of moral integrity. You may well be hired or chosen over people with less exalted degrees because you will be assumed to have a higher standard of integrity. It’s good to hear that you have had a change of heart, and have now developed more integrity, but your college experience itself would indicate that you lacked one of the most critical life skills – the ability to follow the rules as they are set out. Yes, it’s valuable to be able and willing to criticize rules that are wrong, but it’s also important to know how to do things the right way, and crucial for almost any profession to do the work that you are asked to do.
My father drummed into our heads a quote which I have never been able to track down, but which I have taken to heart: “The chief purpose of education is to train the mind and the will to do the work that has to be done, when it ought to be done, whether you want to do it or not.”
Plagiarism and cheating are wrong not only because they are stealing both from the author of the plagiarized work and from the school whose degrees have value, but because they keep the plagiarizer from learning how to do the work that has to be done.