- Code is not prose. It's not read like a book so it's not clear that an "ideal measure for continuous text" is at all relevant.
- Most lines are short even if the limit is more than 80 characters, so you're unlikely to accidentally shift up or down after reading a long line.
- Even if there turns out to be some benefit for reading code based on Saccades, that means nothing unless you can make some quantitative comparison with the other advantages and disadvantages of a longer line length.