It is a bit more involved than a simple rewording, mainly because I
could not find a concise sentence that sounded 100%-unambiguous
(e.g. "literal" might be taken to mean "suitably backslash-escaped or
quoted").

> BTW, I had several use cases where * or ?, don't remember, was not
> isolated, and I wanted to answer "n" to still get the substitution by
> the command and was disappointed that Emacs just canceled.  Maybe one of
> the suggested patches also improves that, I haven't checked yet.

Allowing the user to substitute non-isolated characters is something
Drew also suggested in bug#35564.

I haven't tackled that yet (haven't met the use-case).  What would a
good UI look like?  Successive prompting for each non-isolated
character?  Something like:

> Substitute highlighted occurrence of `?'? ([y]es, [n]o, [a]bort)

Although note that you can already tell Dired that your '?' is meant to
be substituted, by surrounding it with backquotes.  E.g. try to mark
some files, then

    ! echo 'foo`?`bar'

It's not implemented for '*' though.