[foopod]

I heard once that it was because punch cards were 80 columns. But my guess is screen resolution? We have much higher definition screens and can fit more on a line now? Should we have longer lines of code? Probably not. Could we? Heck yeah.

[ams6110]

Yes. Punch cards were 80 columns. Later, Teletypes for the most part were also (I think some could do 132 columns). Then terminals like the VT100 carried this forward (again, some could do more, but 80 was still the default and they added the 24-line convention). The IBM PC kept to this standard also. And in 2017, the "default" terminal window is still 80x24.