You would be free to make that argument in court but courts tend to be a bit more practical in how they approach a problem, probably because:
a) as others have pointed out, ChatGPT is making what a reasonable person would consider a truth claim
b) it’s not entirely random
c) even if it were random as in your example, you’d have a hard time explaining why it was only a few months and not something a bit more like infinity feels to the average person before the defamatory statements popped out. On the balance of probabilities, you failed to implement true randomness or anything like it, and you’d be liable.
a) as others have pointed out, ChatGPT is making what a reasonable person would consider a truth claim
b) it’s not entirely random
c) even if it were random as in your example, you’d have a hard time explaining why it was only a few months and not something a bit more like infinity feels to the average person before the defamatory statements popped out. On the balance of probabilities, you failed to implement true randomness or anything like it, and you’d be liable.