Unacceptable

[Sarah]

Does not meet the standards of The Earl of Lemongrab

[Dianne]

Not satisfactory or allowable.

[Julene]

[Something] [extremely] [inappropriate].

[Dianne]

In the 2000s, when used in a lawyer-created public [apology], a word that demonstrates that the person concerned (eg. a sportsperson) knew their actions would be wrong before they acted, do not regret their actions for one second since, and are annoyed they got [caught out] and are forced to make a public apology to keep their career going.
When used by another authority such as their coach, using unacceptable implies the latter is also annoyed that the former got caught out, is forced to make a public apology and that [the mud] sticks to the authority by association.

[Agnes]

too bad to be accepted, approved of, or allowed to continue: