Comparing screwing around with dental xray equipment (or any x-ray equipment really) to distributing the radioactive bits of chemotherapy equipment across a neighborhood is like saying "be careful, you wouldn't want to accidentally blow up a government office building" every time someone starts talking about plant fertilizer or lecturing someone who's installing 12v car audio about transformer substation safety practices. The magnitude difference between the subjects is so big it constitutes a qualitative difference even if there is a common element.
Not every discussion about something in the physical world needs to start with a low effort comment about how you can die by cranking it to 11 and then abusing it.
In the context of buying used hospital equipment and the concerns of a layman making a mistake due to the very confusion you highlight... Seems at least relevant.
Not every discussion about something in the physical world needs to start with a low effort comment about how you can die by cranking it to 11 and then abusing it.