1. As seen in this coountry, most people did not in fact "pursue physical activities they enjoyed". They got much less healthy and then the white collar machines started to churn their brains too. I do not see this ending any differently.
2. As many have noted (and has been known for decades pre-AI), getting more work done in a modern workplace does not reward you with more of your time back. It gives you more work and higher velocity plans. It may even end up compensating you less. There's only more benefit to this if you are your own boss, and so far a lot of those kinds of people are simply selling grifts, not truly disrupting the industry with newfound efficiencies.
>but we can't force the world to technologically regress just because some people are lazy and don't exercise
I didn't want to go too off topic, but since this is such a sticking point I need to make a big note about the US: most of the world is more sedentary than 100 years ago. But the obesity epidemic is mostly US-cerntric.
Which shows that, while we can't force a diet, we can definitely regulate incentives. But the US chose not to. We had all kinds of initatives to try and regulate what we put in our food and what to subsidize. We instead said corporations can do whatever we want and subsidized chemicals that are heavily taxes or banned in many other western countries.
I know that's a scary word for this community, but this analog of regulations can work here in AI as well. We don't need to ban AI (but I'm not opposed to it in primary schools), but we can shape policy to prevent "corporations can do whatever they want" yet again.