In the future, after all professional writers have been replaced by chatbots, there may be a falling off in interest in reading on the part of humans, because everything you read will start to feel similar and predictable. Kind of like if every movie came from the Hallmark Channel.
The good news is that there will still an opportunity to sell advertising. After all, humans are not the only ones who read. Chatbots also need to read, because that is how they train.
We are approaching ever nearer to the negative loop that Jaron Lanier predicted 20 years ago — chatbots being trained largely on the output of other chatbots. Yet even in that dystopian future, ads will still be incorporated into the training of chatbots, to make sure that they promote commercial products.
This is good news for the advertising industry. Long after most people have given up on reading, ads will still be needed, which means you will still be able to make money in advertising.
Then again, it might be boring work. After all, you will mostly be spending your time training an AI to create those ads for you.