The problem is that these extra payments are used to provide extra benefits, in the form of lower copays and add-ons like dental and vision. Cutting the payments wouldn't necessarily make the retirees less healthy, but it would make them mad as hell. There is no magic pot of money that can be cut without pissing off voters. If there were, it would have been cut in previous hunts for revenue to spend on tax cuts or new benefits.
See Tweet