Every brain in a class is different. They have been processing different input for two decades or more. They have been in different families, workplaces, schools, etc. They have been in different emotional environments.
Some influences are subject to the butterfly effect. For example, a small difference in curiosity can lead to large knowledge differences after a decade.
By economic necessity, Cycourses are written for groups of students, rather than individuals. Nevertheless, it is individuals who learn. No matter how good a Cycourse is, it won’t be sufficient to serve every student in a class.
Skill Cycourses should be flipped. That is, students should read content and do exercises outside of class. Class time should be reserved for giving students one-on-one help from an expert. Student-expert contact should be face-to-face, although synchronous real-time audio and video and/or screen sharing can work (for typical STEM courses, anyway).