Consider a plumber who doesn't understand mettalurgy or electronics but relies on some foundational trade principles that they learned from a mentor and who can understand manufacturer guides for clever new fittings and pumps.

That's the level that most competent software engineers should be working at.

Delegating understanding to LLM's is totally different thing. It's not plumbing at all. It's more like hiring a unlicensed, generalist but well-reputed handyman from Craigslist and then going out to a movie while they do the work. It could turn out fine, or not, and if it does work out, it could even save time and money if they're rate is low enough.

But it's not plumbing anymore, and you should be wary about billing plumber's rates for their work or taking on liability for it if you haven't even made sure that work meets your own standards of trade and quality.

You can argue that it's "one more level of abstraction" but it's a qualitatively different kind of abstraction. And in the economy of skilled labor, and the legal landscape of accountability and liability, that difference is enormously relevant.