Modern technology has changed the way people work and live. Technical expertise is now important for many career paths. Careers where people accidentally acquired a skill and expanded on it have been replaced with formal learning expectations. Decades ago, programmers and IT specialists were often people who learned on their own. Once they acquired a basic skill or two, they were then promoted to a specialist job. That is no longer the case in large companies. Programmers and IT specialists are often required to have a degree before being hired. This is true with even the lowest entry level position.
Scientific progress in other areas has added new fields to the number of careers that require degrees. The science of demographics has become a well defined area of expertise. It no longer includes a large margin of error where a lucky guess can make or break a marketing career. Modern demographers use algorithms to define their parameters and come up with exact numbers. This has changed the way large and small companies view marketing careers and has changed hiring parameters.
In the past, many people landed careers in marketing because they were good with numbers, advertising or were creative. Modern marketing jobs are now considered a graduate career. The science of demographics has enhanced marketing abilities to the point where learning these enhancements requires a formal education. Students majoring in marketing may occasionally do intern work to enhance their degree, but a career in marketing now requires they finish their degree before doing original work in the field.
The world will continue to change as technology and new sciences expand the parameters of human knowledge. As these changes take place, more and more fields will become restricted in their entry levels. This will allow more people to aspire to graduate careers in non-traditional fields.