On unis, DH has been marking first semester exams for a first year undergrad course. This is the 4th or 5th year he's done it, so he's seen a wide range of student abilities and so on over his time. He's been tearing his hair out because this year is a disaster... they're really struggling to pass a huge proportion of the year group, and even those who have passed are only just passing - only about 10% have got As, whereas usually it would be about double that. It's not just his teaching

because there's a group of them doing the course, and it's not just the online nature of the teaching/ exam because last year (Sept 20 entrants) also had online teaching - and more of it too... this year they've at least managed in person workshops/ tutorials.
The only thing they can narrow it down to (and this is reflected in student comments too) is that they just haven't done proper exams before, and also have much lower basic knowledge/ skillset in general techniques that they should have learnt at higher level. This is the cohort that would have had higher and advanced higher years disrupted, with the faff of the teacher-assessed work being fed into algorithms, reduced curriculums, constant class tests on what they've learnt that week and so on. It seems to mean they're not able to take that knowledge further, combine sections of teaching into a more complex problem and so on. Even the language of the formal exam questions seems to have thrown them, whereas they've been coping fine with the more informal workshop questions on defined topics. This just wasn't something that he and his colleagues had considered would be an issue, so hadn't done any special exam prep stuff, beyond what they would usually do.
They obviously don't think it's fair to make so many students pay to resit/ retake the year for something that really can't be seen to be entirely their fault. So they are putting on extra basic classes to cover bits of the syllabus that seem to be a black hole, and do work on "exam thinking" . But it is true that having 2 years of disrupted education has affected the students, at least in his subject. And it's not even something "important" like medicine or dentistry... I really wouldn't want to let medics with huge holes in their knowledge/ understanding loose on the general public.