I hope you don't mind if I believe the word of people who were actually involved with this over some rando on the internet second-guessing them 30 years later.

Pipelines are already filled with all kinds of electronics.

https://www.slb.com/products-and-services/innovating-in-oil-...

An oil filled anything has always been the gold standard to run wiring through. It’s insulted, temperature regulated, vibration resistant etc etc. also a huge pain if something does break … lol which fortunately is unlikely !