And the author of Shvus Yitzchak was paid off by whom?
It happens to be that I originally thought like you do, that to to say there’s melachah mamash doesn’t make sense, considering all the devices used for refuah/bitachon, but I looked into it, and there are some very legitimate, apolitical sources to asser here, and they’re more compelling than the reasons to be mattir.
Even Rav Shlomo Zalman, who held electricity is d’rabbonon and was mattir these devices, only did so out of great dochek, but in some places writes that it should be a direct melachah if the device us made to do this.