I think your broader point is generally true and often missed so have an upvote, but in this case the FDIC is going beyond it's stated policy. Demanding that the floor of the FDIC's guarantee be lifted/ignored seems distinctly anti-libertarian regardless of whether it was the right thing to do practically. Draining a substantial portion of the FDIC's insurance program's funds seems anti-libertarian. Refilling that portion through (likely) additional requirements on banks that didn't have these issues seems anti-libertarian.

I guess you could make the broader point that people comfortable with government intervention would have argued for full depositor guarantees, so in some since libertarians are playing the same game but that seems much more tenuous to me.

Per your general point, it was very well written! I like to say that you aren't a hypocrite for playing by the rules of checkers even if you wanted to be playing chess but were overruled.