open science - Why don't publication venues systematically make the LaTeX source of papers available? - Academia Stack Exchange

"I wonder why most publication venues don't systematically make the LaTeX source for published papers available? (which implies systematically asking authors for the LaTex source) LaTex source are more machine readable than PDFs, and make it easier for humans to reuse part of it (e.g. math equation or figures), amongst other advantages. I fail to see any downside...."