When I think someone has gone over the top, I reply off list. I try to
do this with off-topic stuff, unless I really think it could be of
interest, or if I am the one looking for off-topic information. Then if
I am ignored, it is a little less ego bruising, but I have also gotten
some great responses this way (and am now on a Maestro list). OTOH, it
is gratifying to have someone suggest that what I sent them is likely of
interest to the list.

But I would rather not be dressed down on list, or see anyone else be
told what for on list. Even if their injury was to the whole of the
list, I would rather see them apologize in response to off list
correction, and if they are not inclined to admit their mistake,
correcting them on list probably won't help. Maybe I'm wrong about this;
if you think so... well, tell me off, off list.

my $0.02