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I find that when writing text as input to another program, any command substitutions in double quotes within the intended text are interpreted and expanded by the shell

The links in the answer here states that single quotes can be used to prevent parameter expansion or command substitution. However I'm finding that enclosing a command substitution in single-quotes also fails to stop the shell from expanding the command substitution

How do you prevent the shell from interpreting command substitutions that are intended as text rather than a command to be executed?

A demonstration

$ echo "`wc -l *`"

attempts to count lines in all files in the current directory

$ echo "'`wc -l *`'"

Same result, i.e. counts lines in all files in the current directory

update From this demonstration I've spotted that the problem seems to be that I am quoting the single quotes. I think enclosing single quotes and ` (backtick) in double quotes preserves the literal meaning of (i.e. suppresses) the single quotes but does not preserve the literal meaning of the backquote (i.e. backtick) that introduces the command substitution.

In my use case the input for another command needs to be quoted. With this document saying that:

A single-quote cannot occur within single quotes

How do you prevent a single-quoted command substitution from being expanded when the single-quoted command substitution is within a (double) quoted string? There should be a way to do it other than using backslash escapes

Use single-quote strong quoting:

printf '%sn' '`wc -l *`'

And if you want to also include single quotes in that argument passed to printf, you'd need to use different quotes for ' itself like:

printf '%sn' '`wc -l *` and a '"'"' character'

Or:

printf '%sn' '`wc -l *` and a ''' character'

Other alternatives include escaping the ` with backslash inside double quotes:

printf '%sn' "`wc -l *` and a ' character"

Or have ` be the result of some expansion:

backtick='`'
printf '%sn' "$backtickwc -l *$backtick and a ' character"

Also note that:

cat << 'EOF'
`wc -l *` and a ' character and a " character
EOF

to output arbitrary text without having to worry about quoting (note the quotes around the first EOF).

In the fish shell, you can embed ' within '...' with ':

printf '%sn' '`wc -l *` and a ' character'

but anyway ` is not special there, so:

printf '%sn' "`wc -l *` and a ' character"

would work as well.

In rc, es or zsh -o rcquotes, you can insert a ' within '...' with '':

printf '%sn' '`wc -l *` and a '' character'

See How to use a special character as a normal one? for more details.

You can escape the backticks by using a backslash as shown below:

echo "`wc -l *`"