The special naming convention is mostly used as a form of elitist gatekeeping; it's a tribal shibboleth. You should be able to figure out whether someone is talking about latex (polymer) or latex (markup) from context, so having a special naming convention is rather pretentious and superfluous. If calling it lay-tek was important, they should've called it laytek. Historically, as I understand it, distinctions between the written and spoken forms of words were used as a form of gatekeeping between elites and commoners. Same goes for arXiv.

The great thing about language is that you can just change things if enough people play along. Call it gif or jif, arxiv or archive, latex or laytek.