I suspect going to a university is helpful in most STEM related fields. In anything medical or law related you don't even have to think about getting a job without a degree. I don't see how anyone can compensate an economical or business study by doing project on their own.
If anything I think IT is an outlier, because not going to university and learning the subjects you would have been taught on your own might be a valid option.
Law and medicine are the poster child for credentialism, you are forced by law to complete the degree to work, even if most law and medical professionals will tell you, work has nothing to do with college.
They suffer the “driving license problem”, having the title says nothing about your competence.
For instance, pretty much everyone has to study trigonometry, but very little people actually need to know trigonometry to do their job. In that sense technical fields are an outlier, because knowing trigonometry actually matters to your career.