I think the opposite will happen. Engineers will still be worth $200k/yr.

Humankind will just develop a lot more software, faster and further into industries.

Availability will create new demand.

I think you have that backwards (sort of). The high tier programmers who can write things AI can't will be worth more since they'll be more productive, while the programmers below the AI skill floor will see their value drop since they've been commoditized. We already have a bimodal distribution of salaries for programmers between FAANG/not, this will just exacerbate that.

I suspect you're right, but I think it'll follow the COBOL engineer salary cycle, engineers that have a deeper understanding of the whole widget will be in demand when companies remember they need them.

As somebody who makes extensive use of LLM’s, I very much disagree. Large language models are completely incapable of replacing the kind of stuff you pay a developer $200k for. If anything they make that $200k developer even more of a golden goose.