@anotherglass All the very best to your DS for his upcoming interviews.
It is so hard and, amongst some good advice, some of the responses on this thread have been less than helpful. It's almost as if you were somehow foolish or unreasonable to have hoped? Anyway...
I would like to touch on the psychological aspects. I had an early window into the current horror show by job-hunting myself a couple of years back. In that time period the ONS job vacancies figures fell over each successive quarter... A wider economic phenomenon is happening and the techniques/approaches of yesteryear will not work if the jobs simply aren't available.
Those who don't believe it simply haven't experienced it for themselves, yet.
What helped me to deal with the demoralising effect of job searching:
Restricting my usage of the job sites - only searching on a Monday and devoting the rest of the week to applications or other constructive activity. Otherwise it becomes another form of doom-scrolling.
Applying in batches, so I always had a live application in early stages while interviewing for another. So if I didn't get one then I had something else to hang my hat onto!
Trying not to overly invest in any one job, which is tricky but probably important.
Ideas:
How about some self-presentation skills training for 1-1 interviews? By that I mean, 'how you come across' rather than 'using Powerpoint.'
Sorry to ask, as it's a sensitive point, but is his grooming good? It is easier for men than women but I also think standards can be more exacting in terms of haircut, shaving, eyebrow hair-trimming and skincare. What is fine on campus might not fly in the workplace. It hasn't been mentioned on the thread so I thought it might be worth mentioning. Plus investing in some good lighting for video interviews.