Given this statistic from a recent McKinsey report, “Approximately 80% of the U.S. workforce could have at least 10% of their work tasks affected by the introduction of GPTs, while around 19% of workers may see at least 50% of their tasks impacted.” Please share your thoughts on: what would you expect us (humans) to do with all that extra time?

Well as on date; Chat GPT can take over some define tasks only. I believe change is the only constant. So, be part of it, accept it and most importantly please change yourself (upgrade) as well to be relevant in the world.  

Learn, and focus yourself on those things you don't know and will provide value to you, to your department, and in the end, to your company. Be curious to understand that time is a commodity and that if we waste it, it won't go back, so lead your knowledge hunt to acquire more information that with the help of ChatGPT will be consumed faster and effectively as well.

Technologies are rarely disruptive in the long run.  

The world adapts.

Look at the world-changing disruptions during the 1900's, most of them are now so common, many are considered inconveniences(long wait at the airport).

Cars, Planes, Phones, most medicine, agriculture (modern automation or just modern fertilizer)

AI will disrupt us now, but eventually, and sooner than most think, we'll adjust and fill up our lives with new and different tasks just like we always have.

Do human things. Spend more time learning, critical thinking, and being more creative, imaginative and intuitive. Do more leading, communicating, and developing your coworkers. Work on the business instead of in the business!

Higher value work, offloading task work to the GPT. More productivity out of a workday, with an always-on asssitant to help with almost whatever you need. More time to think about big things, innovate, and make a bigger difference, without having to most of your time doing the "keep the lights on" work.