The Apple II series could power many more external drives than any compact Mac model could. You could easily put 3 external floppies on most Apple IIs, but you couldn't do that on the Mac. I assume therefore that the Apple II has a higher floppy drive output current. In such a case, I would assume that you might damage your compact Mac by trying to power this hard drive from the Mac's floppy port.

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The Apple II bus could provide an awful lot of power for 1977 requirements. The Disk II drive has many moving parts so it is reasonable to assume that it uses more power than an 800KB 3.5" drive. The bus is powerful enough to run a Silentype thermal printer.

By the time the IIgs arrived, expansion cards had grown bigger (more chips) and there were some that drew a lot of power (eg IIgs accelerators and sound cards). The ability to deliver enough power on the expansion bus then became a tricky issue. I'd be reluctant to power a disk like the one above from the floppy port on a heavily expanded IIgs. Ditto, a Mac floppy port.