Nope. Writers write. Most writing is "economically worthless" — the number of novels that get written every year is astronomical versus the number that make money. If we were to let the market judge the quality of creative works, we'd be culturally fucked.
The writing skills that became worthless for this guy were the ones that weren't worth much to begin with.
Exactly. The market price for anything is determined by both demand and supply. The demand for good writing is relatively unchanged. The supply is also relatively unchanged. In the case prior to ChatGPT that demand and that supply were somewhat low, or as you say - not worth much to begin with.
Oh sure, there's always the Stephen King's and Tom Clancy's of the world, but guess what? They were always the exception anyway and they will continue to be. The same argument can be made for musicians.
Stephen King has written so much by now, his new books are basically remixed versions of his old books. Stephen King has become his own ChatGPT.
(No accident either - the guy is a writing machine - 30 pages a day, no breaks, that's over 50 200 page books a year...)
We're not disagreeing, you're just talking about something different than the topic of the OP.