Honestly, this tracks with what I've seen. Fine-tuning works great if you have a narrow, stable problem and the operational burden doesn't scare you. Most teams don't have that.
The version management alone is a nightmare. At least with prompt engineering you've got readable, git-trackable instructions. You can A/B test variants without rebuilding infrastructure. When something breaks, you can actually reason about why.
That said, there's a middle ground nobody talks about: retrieval augmented generation with a solid vector store beats both approaches for knowledge-heavy tasks. Keeps your domain knowledge current without retraining.