Which leads me to suspect that if there were a demand for "a big file to source in your bashrc to alias 'cp' to 'copy'", it would exist. It is not exactly a difficult thing to do, but nobody actually cares enough to do it (probably because it is not actually a problem).
I suspect people get used to cp, mv, etc, and then aren't interested in longer versions anymore. I'd still say it'd be a good default.