I’ve received MRI data by both CD and online. I think it just comes down to what systems the hospital/consultant supports and how recently their systems were set up of modernised.
It just really irked me that people got CDs instead of being fully digital. The last time I used a CD (besides my PS4) was 10+ years ago. I don't even have a CD player anymore. I'm sure Gen Alpha will look at CDs the way I look at floppy disks.