Surely it will also free people up to apply their intelligence (or stupidity) towards other things.

It's concerning because there is already way too much 'intelligence' in this society and most of it is used to propagate falsehoods, irrationality and to manipulate others in counter-productive ways. I hope AI educates people and doesn't merely steer them down deeper into their echo-chambers. That said, I also really hope that AI doesn't just bring everyone into alignment and agreement about ideas which aren't true. There are significant threats with both extremes.