Sort with case-sensitivity in macOS in the Terminal

Question

I am trying to use the answer in GNU Sort by case-sensitive to sort a file in my Mac OS.

My file.txt looks like this:

"Best"
"A"
"BEST"

In the second answer to the mentioned question, it says that one can do:

echo -e "d\nD\nc\nb\nB\na" | sort --ignore-case file.txt

and the output should be:

"A"
"Best"
"Best"

However, when I do it in my computer, I get:

"A"
"BEST"
"Best"

It does not matter if I use the --ignore-case or not, the output is the same.

Maybe LC_COLLATE=C can not be set in Mac OS?

Does someone know how to use sort and have lowercase < uppercase in Mac OS?