They very likely do. On the M: and Z: drive.
As far as I can see this is just IT saying “if you stored your data somewhere you shouldn’t have, it’s now gone”.
But of course they can’t say that, so instead they have to help people recover from their mistake.
Or maybe the mistake was thinking people would actually do what you told them instead of whatever was more convenient.
You're assuming people are aware of where they — or their niche specialty software packages — store their data. I'm not even sure I'd know where e.g. some biotech-DNA-analysis-package stores its data.
Recently I've been given incredible abuse by my ex who accused me I took her external HDD when I moved out. I actually considered I did and scoured all my boxes and belongings and even invited her over to search herself. Meanwhile, I asked her if she had any backups.
Needless to say the abuse tripled. I never found the drive.
Why didn't IT use their powers to deploy a backup program before they deployed a deletion program?
Thought expermiment: what wuodt happen if a student accidently deleted school's files, instead of the reverse? Criminal penalties? Civil penalties?
Were these personal laptops, or university provided? The fact they have H: and M: drives mounted suggests the latter.
Which is actually not safe for cold storage in any way, shape, or form. Cheap flash storage devices are optimized for minimum cost per bit stored, not long-term data retention.