[dexen]

>I wonder if GPT4 or 5 (hypothetically) will allow these businesses to fire most of their workers.

The real inflection point is slightly different: when we switch from human preference to AI preference. Let me explain:

The current "gold standard" is human-created content. At present you have humans, algorithms, and AI on both sides (newspapers, Google) trying to out-wit each other by, respectively, pretending to be humans writing content, and by detecting non-human writing.

At present the humans are a necessary ingredient, and combination of algorithms and AI is unable to match the value.

However at some point the algorithms and AI writing content quite possibly will exceed humans' - and so Google and the likes will start prioritizing the machine-created content over the human-created content. Once that tipping point is reached, you can expect a somewhat rapid flip in content authoring. The funniest part of it is that we might not even become aware of the flip for a while - due to the sheer complexity of the algorithms and AIs that Google employs to grade the content.