Maybe it's not what you intended, but to me you seem to be proud of your ignorance about a piece of software that's part of computer science history. Instead of writing that comment, you could have learned something by reading about TeX on Wikipedia.

Because people do not care about their TeX interpreter. Today, nearly every LaTeX writer uses pdfTex. If they switch to luaTex nothing changes, because luaTeX is (intended to be) fully backwards compatible. If you start writing your own packages, then luaTex becomes interesting.