“Just curious. How did pipelines work before the internet?”
Exactly like everything else, except for the internet, which didn’t exist.
There’s a very interesting video from AT&T about how they helped pipelines operate back in the 50s or so. At the time they created basically a promotional video of how their services could help pipelines, railroads, businesses, etc. operate and since then they’ve posted several of them to YouTube.
Automation replaced the personnel of the former command and control system.