The structure of a good argument would be something like: certain tasks are fundamentally human and impossible to automate (which and why?) and by pushing AI use beyond what is optimal you are actually hurting your employees ability to do those hard parts.
A weaker but still useful argument is that most everything can probably be automated, but frontier models aren't there yet.
> "There's always an easy solution to every human problem; Neat, plausible and wrong."
-- H. L. Mencken
It's like the classic scenario, where you lash-up a barely functional UI demo, and the manager cuts your development schedule by 90%, because you "already have it working." That taught me to never do a lash-up demo. If I show something to someone, it is ship-quality (but often incomplete). It's a technique that I've used for years, and is a great way to involve nontechnical stakeholders, without risking stuff like "it's already working."
All that said, I think that AI definitely could automate a lot of the repetitive stuff involved in shipping. It's just that the CEO would fire the folks that could teach it, before it can learn, because they think that what they do, is "unimportant."