The reason he, and others, are "retiring" from tech now is because they have the wealth to do it, in big part due to being at the right place at the right time in life. That’s it.
AI has nothing to do with it, they just want a small ego stroke.
The end result of it is that the average dev position becomes seen as dispensable, competition goes up, workload goes up, compensation stagnates.
Being able to escape the rat race and retire is a privilege though. The rest of the rats gotta keep running faster and faster just to stay in the same place.
I'm fortunate with regards to the timing and being able to do it, but if I could have a job like the one I had ten years ago I'd still be working.