> SREs should configure their infra by hand sometimes to not lose that skill
Actually... yeah, I'd totally say that. Some SREs in my company never wrote a single line of HCL that wasn't a call to a in-house, pre-approved module. They think they know Terraform - they don't, and they don't know what's under these modules either.
I don't even have experience with Terraform at all...
I'm using something different myself: a Docker Compose + reverse proxy config + some other support files, pushed to a private GitHub repo, which then triggers a GitHub Actions workflow that leads to the repository being pulled on the VPS and the infrastructure to be "rebuilt" (docker compose up, reverse proxy graceful restart).
It's unclear if you even know what terraform is, because the system you described has little to do with it.
Terraform would be the code that brought that VM into existence.
Terraform, as with any language, is mostly useless for humans now. It is for the agents full stop. You are correct though, we need to know the underlying architecture and most importantly why it is the way it is.
That is not true of Terraform, nor any other language. If you aren't at minimum reading and understanding the code, you are bad at your job, full stop. More realistically, you should still be writing a lot of code, because most of the time you will waste more time trying to work with LLMs than doing it yourself.