Are you saying that the equivalent of pulling the plug on the drive does the same thing and is safe?
When I was first worked on drives, an unexpected power loss would literally throw your entire hand out. When first observed, I thought that was dangerous. Even that power loss was not harmful - to hands.
Drives have always worked that way. Once the drive sees power dropping, plenty of power remains inside to completely anything that must finish. Even disk drives that used motor oil had enough power to finish.
Although hardware can never fail on a power loss, some early file systems might lose data. FAT filesystems were a notorious early example. If a file save was interrupted to an FAT filesystem, then a new file would be lost. AND (worse) a previous copy of that same file also might be deleted. FAT filesystems explain those 'refuse to die' myths. With HPFS, NTFS, and other filesystems (ie 1990), filesystem problems were eliminated. If a file was not saved, its previous version was restored.
Power loss, to computer hardware, takes forever. Even its power supply is required to keep operating for a long time after power is lost. Therefore a UPS switching from AC mains to battery (a period of no power) results in no computer interruption.
