Is that in the US? It would make some sort of sense since 'moot point' has effectively reversed its meaning in US english ('something not for discussion' there

Is that in the US? It would make some sort of sense since 'moot point' has effectively reversed its meaning in US english ('something not for discussion' there). 'Mute' seems to to agree with that sense. (See also the US meaning of 'table' as in 'postpone for discussion' which has also reversed)