There are 2 issues there

1 - yes, screens are huge, but it doesn't mean people can/will use small fonts or will scroll the screen

With today's big/wide screens it's more useful to have code side by side.

2 - Abuse. The 80 character limit is a pretty good indicator that you should be doing something else instead of having your code go over 80 characters.

Long lines are confusing, and you most likely can split the logic in several lines, facilitating maintenance.