It's bad enough that public high schools have not prepared students for 4 year colleges and universities. That has been the case for at least 50 years IMO. I still remember my first two weeks of college, nearly 50 years ago. I was terrified, seemed like everyone I met was in the top 1% of their class.
My daughter is a 3rd year at university and her school seems to be trying hard to make “distance-learning” work. Particularly as you get deep into a major, everyone is learning that group interaction, specialization, hands-on training, etc… is very difficult to transfer on-line. Internships have stopped. Meetings with industry professionals have stopped. From what I would guess, I would say class work has been cut down 20-30% to allow for the on-line format (fewer projects, reduced office-hours with teacher, etc..) It works OK for now, because she already knows the professors, knows her classmates, class style and culture were in place since January, and they had formed into work and study groups before Coronavirus hit.
NONE of that would exist for an incoming freshman. As you point out, literally everything is new, and it would be extremely difficult to make the jump in expectations, work-needed and competition from others with a pure “on-line” format. Beyond that, they would lose the life-long, memory forming events of making new friends, going to the first homecoming game, etc….