I further wonder, however, why a person might decline, say, to push a button that made them permanently happy but left them unable to interact with the rest of the world, have any meaningful thoughts, interactions, accomplishments, etc.
This is not the case he's talking about, for there is no question of erroneous predictions of happiness. By fiat, you will be happy if you push the button, for however many years you would have lived, but your present self will be very disappointed in your (blissfully apathetic) future self for not advancing the cause of Science or somethin' like that.
Now I want to think declining to push that button is philosophically defensible, but I must admit I don't really know how to defend it. I know I don't give a shit about whether that button-happiness is somehow "inauthentic happiness". I know my gut sense is the same even if you replicate it at global scale, e.g. would I prefer that the whole (human) world was permanently happy at the cost of ceasing to figure out what the deal is with the universe we inhabit? I think no.
Fundamentally this is a stupidly simple issue --- what sense does it make, if any, to want a want --- but it's been particularly gnaw-at-the-back-of-my-mind-y to me for most of my life, come to think of it.