We hear this line all the time, but it's actually a really, really bogus argument.
Government officials can "opt out" of things all the time if they disagree or can't do something in good conscience. In the military, there are conscientious objectors who can "opt out" of certain types of service if they are pacifists, etc. Indeed, since the law changed *after* she had already been elected, the argument that she either needs to violate her own conscience or else "find another job" sounds dangerously close to violating the Constitution's ban on religious tests for office - in short, you can't tell someone that they have to violate their own conscience before they can hold a government position.
In the Founders’ time, a general biblical ethic was considered to be a normal and good thing, not a specially “religious” thing.
If there was a failing, it was in assuming that this would always be the case.