I don't like him as a candidate, so I'm not bothered that he's getting his turn on the hot seat. But I also saw somebody frame this issue in a way that I think is more meaningful than my spite. Though spite is also a perfectly valid reason.

There's a real possibility that the stuff that he did working for McKinsey was shady and immoral. This is because a lot of their work is shady and immoral. Hiding behind an NDA may work for the early primaries, but it's clearly not a tenable position for somebody who wants to be president. Additionally, there are people who know the answer to the question of what he was doing for McKinsey in Afghanistan and that means it's going to come out eventually. Do you want to find out what that is now? Or do you want to find out what it is in October of 2020?