No need for any defense or attack.
Your post was (in approximate words): "to build LuaJIT requires Lua to be installed"
Based on the limited knowledge in that post, the only advice possible was to recommend that you match versions.
If your post had been (as it now is): "Lua is required to run parts of the build process"
Then the answer would have been different.
I.E: Garbage in, garbage out.