Proper programming language that is not meant to carry old silliness such as "oh back in the day memory was important so you have 256 registers" or "fixed point arithmetic should be fine" or "it's meant for typesetting don't use it for complicated stuff so a figure can float 15 pages whatever".
We have PDF as de facto media for handling output and text files for holding the source files. Better TeX means we are not using an archaic madness to go from Txt to PDF but able to utilize modern IT tools.
TeX is just old and died decades ago. Academia is holding it as a hostage because papers...
Disclaimer: ex-academician and a low key maintainer of TikZ
Edit: TeX as a language is horrific exactly what you would you expect from a computer scientist so it's not that Knuth is to blame, it's the rest that didn't get his vision such as academia still leeching off of it instead of using taxpayer money to generate a proper tool