If writing is thinking then what happens if AI is doing the writing and reading?

Writing isn't necessarily thinking. For example you can have a spreadsheet of 20 000 words and use an algorithm to randomly pick a sequence of words. No one would call that thinking, even if such a process made intelligible sentences sometimes.

"AI" is using an algorithm and statistics in the same way---it's just more accurate at making intelligible sentences than the example above. I wouldn't call either thinking, would you?