More predictable maybe, but also way more intensive (only 30-60 seconds between trains, vs rural freight where many lines only see one or two trains per DAY, or even per week.
Rarely used freight lines (aka branch lines) would never be automated, that wouldn't make sense. And some mainlines (I live near one) see as many as 4 100-car freight trains per hour. Those will never be less than one-man operation either, not least because at-grade crossings are everywhere.
All that means is that you design the system very robustly. And, of course, trains fail-to-safe. Cut a brake line? Train can't release its brakes. Signal out? Conductor can only move in GoA0 (manual), at reduced speeds, until the next signal is reached (and readable). Etc.