Most people pursue it because they enjoy writing and/or because they have a dream of writing a great novel and being applauded for it. Of course some hope to win the jackpot of having a massive bestseller on their hands.
But there's also an element to it of writing a story we'd like to read that doesn't exist, and there AI tools might well end up replacing actually writing. Especially if it can riff off your feedback in more of an interactive fiction way.
As well as being able to get plausible expansions of the work of an author you like who is no longer writing (and that is where the most obvious commercial appeal for AI writing is - any given average book earns next to nothing, but even a third rate ghostwritten sequel in the name of a bestselling author can earn a fortune; expect publishers to start trying to sneak clauses about being allowed to generate sequels if/when the author fails to produce new works into contracts)
That said, there'll still be a space for human art for the reasons you give, and a lot of the market for content is similar - we pay for the stories behind the art as much as for the art.
But there's also an element to it of writing a story we'd like to read that doesn't exist, and there AI tools might well end up replacing actually writing. Especially if it can riff off your feedback in more of an interactive fiction way.
As well as being able to get plausible expansions of the work of an author you like who is no longer writing (and that is where the most obvious commercial appeal for AI writing is - any given average book earns next to nothing, but even a third rate ghostwritten sequel in the name of a bestselling author can earn a fortune; expect publishers to start trying to sneak clauses about being allowed to generate sequels if/when the author fails to produce new works into contracts)
That said, there'll still be a space for human art for the reasons you give, and a lot of the market for content is similar - we pay for the stories behind the art as much as for the art.