Sure, copywriting seems to be pretty much irrelevant now. Same with image generation wherever you can get away with it. The quality may be reduced in many cases but the cost is absolutely a fraction of what it used to be.
You fire the copywriter, but you still have to pay for the advertising (google clicks, tv spots etc).
So if you have $100,000 ad campaign and you use AI instead of paying $10,000 to the copywriter, you probably have a higher chance of wasting the $90,0000 ad spend.
So it comes down to, the AI probably makes a skilled copywriter better. But you can't get rid of him