bug#36206: [PATCH] Change `user-error' docstring from "pilot error" to "user error"

[Drew Adams]

> > Right, but we are now discussing the term "pilot error".
> > Do you think that it is better than "user error"?  If
> > yes, why?
> 
> History. Community. Cultural background.

"Pilot error" is better not for those reasons
but because it more precisely (exactly) says
what the cause of the problem is (as I said).
But that's not important enough in this
context to allow confusion by readers
unacquainted with it.

As for history, community, and culture -

This is not much (if at all) about _Emacs_
history, community, and culture, IMO.

The history, community, and culture where the
phrase was born, nurtured, and raised is mainly
a U.S. military-industrial one.

There may have been a time long ago when coders
as a social group (of men) were fairly close
culturally to the military, the aerospace, and
naval industries (the infamous m-i complex).
(For decades more code was in Cobol than any
other language, and not just because it is
verbose.  That may still be the case!)

But that's less true now.  Coders as a group
are not so close to that world.

It's still the case that inquiry into a plane
crash will mention "pilot error", and the phrase
is definitely known widely.  But it's not a loss
if we drop it in favor of the clear-enough "user
error".

Emacs will lose nothing, IMO, in terms of its
history, community, or culture.  It will gain
by being more welcoming to users coming from
different histories, communities, and cultures.