Charlie,
the outcome does not make it right, the fact that there were no leaks (that we are currently aware of) does not mean that this is a nonissue.
even the in his statement, the FBI director had a lot of negative things to say about what Hillary did, so much that it is left to wonder why she is not prosecuted.
No one has ever used the small C as an excuse of not realizing that this is not confidential, what Hillary repeatedly said was that what she did was legal and there were no emails that were marked confidential at the time.
despite it only being a small number of emails, each of these emails have email chains and we now know that what she did was careless and against the rules.