alt Hacker NewsDrives? I havent seen one yet. Floppies yes, but just like SD cards its just a plastic piece being read by controller GPIO and a mere suggestion to the hardware.
There are forensic Write blockers for drives tho starting at around $200 for SATA/IDE solution.
Some of really old SCSI and (I think)IDE HDDs did have "WP" jumper positions. I don't know practically how it was implemented, though.