“There’s no simple “undo” function ...”
Doesn’t need to be simple. People coming into the streets in protest, the software not working, doctors refusing to participate.
Undoing Obamacare will happen by sheer force including the force of the voting booth.
Yeah...that breaks stuff...but the mechanisms to repair/restore in a timely manner will have disappeared. — which is the other part of UNDO.
Also, I recall hearing the same argument in 1992. That didn’t exactly turn out well either.