Students need personal help when learning skills. However, that doesn't mean they need personal help for everything. Further, the people giving the help can be made more productive than they usually are, by unbundling their work, and focusing IT support on labor-intensive processes, like grading.
How does this happen? First, all students use the same website. The site has learning quality designed in. It offers experiences that improve skill learning, like worked examples, and metacognitive pauses. The cost of adding another student to a website is small.
Second, instructional labor is divided between instructors, graders, and potentially other roles. Graders are low-cost casual workers, with just enough expertise to follow a grading rubric. Instructors don't lecture. They focus on student motivation, helping students struggling with exercises, monitoring student progress, and giving exams and grades.
Instructors in introductory courses don't need to be domain experts. Nor do they need to be educational experts. Student success depends more on course structure and practices, rather than individual instructor expertise. This reduces student performance variance across instructors.
That doesn't mean that instructors will have no effect on student performance. In fact, it may be that the best instructors are those who are caring, empathic, and organized.