You really shouldn't use the absolute hellscape of churn that is web dev as an example of broader industry trends. No other sub-field of tech is foolish enough to chase hype and new tools the way web dev is.
A “few hundred lines of code” in Rust or Haskell can be bumping into multiple issues LLM assisted coding struggles with. Moving a few buttons on a website with animations and stuff through multiple front end frameworks may reasonably generate 5-10x that much “code”, but of an entirely different calibre.
3,000 lines a day of well-formatted HTML template edits, paired with a reloadable website for rapid validation, is super digestible, while 300 lines of code per day into curl could be seen as reckless.