Is there is any definitive research that attempts to answer what character counts make the most human readable line lengths for programming code (typically mono-spaced font, high liklihood of small font size) when considering, in particular, the fact that code bases are very often shared amongst many people; and also the unusual way it looks when compared to other forms of text based communication, such as prose or poetry.
While there's no definitive answer, reading code is still reading just like any other text and some guidelines indicate that 50-75 characters per line is a good number for English.
The cognitive load of code is often far higher per line than it is in English so you probably want to err on the shorter side. I haven't seen any research on the specific column number after which we start to lose focus when reading code, but I imagine it varies significantly based on programming language.
This would be a very interesting research topic.