We could argue this into next year, but IMO the best answer is for
configure scripts and/or makefiles to check for all (5?) of the common
possibilities.
I already do in my scripts; the thrust of my comment was about systems
that do not allow multiple versions of Lua to be installed at the same
time. I simply mentioned that it's probably the better of the evils to
change such places to using Debian's styling, as as you have already
discovered, people assume this is "the one" because it's so common.