But I guess they won't write good novels till they have human level understanding of the world and people which may be a while. Twenty years maybe?
No one is even really trying to teach computers the basics of the world that we take for granted. And it's quite possible that computers will have to be many, many times larger than today to capture the necessary computation that happens in our brains - since a single neuron is itself a computer, and the interconnect seems to be much more complex than an ANN.
Let's remember also that evolution took a good few million years to train our brains (though of course that is not directly comparable to a guided training process).
Language is a mechanism that we use to express a thought (sometimes externally, but most of the time internally in our own minds). A major part of language is an understanding of the world you are "talking" about. And yet, GPT-3 has no idea about the world, it just knows that the words "the sky is blue" are more likely to appear in a corpus than "the sky is yellow". Even more deeply, it has no notion of what an object is, and how it might differ from an agent, what movement is etc - any of the things that make up our shared human model of the world, that we talk about.
Until we can codify such a model (or automatically learn it), we won't be able to say that we have a model that "understands language". The GPT people are not even trying to look in this direction: they are throwing more text and more neurons at the problem and claiming it will work. They'll probably end up with a model that can essentially do the equivalent of instantly finding the best Shakespeare quote for any situation you throw at it, but still won't be able to reason about that situation in any way, or keep a story straight.
This is already visible in GPT-3: its output (even though most of what you tend to see is carefully hand-picked out of a soup of more meaningless output) meanders around without any point to make: it simply does not have a point to make, and it cannot have a point, by the very nature of its construction.
Essentially, language is words + context, and GPT-X only has access to the words, with none of the context. And furthermore, no one is even working on thinking to add the context yet.